An Overview of Database Management System

Transcription

1 q E An Overview of Database Management System Components of an Information System One of the most important functions of any computer system is to provide powerful tool for management of Information System of an organization, in which raw data (Transactions as inputs) is processed to produce meaningful information (Reports as output for different levels of management). The processed data is stored in the form of data files usually referred as Databank. This databank becomes one of the sources of knowledge management required for decision support for monitoring various activities as well as strategic planning etc. Thus components of an Information system can be categorized as follows: Transactions Processing System for processing raw data Management Reporting System to provide relevant reports to various levels of management Decision Support System for management activities like, monitoring & control, decision support and strategic planning etc. Executive Information Systems for senior executives In the real world environment, Information flow in the organization is horizontal (between various applications) as well as vertical (across hierarchically organized departments / branches etc). Thus in an organization, Information System can be designed at different levels as follows: Individual Applications Level Department Level Organization Level Intra-organization Level Training Division, NIC, New Delhi 1

2 Efficiency & effectiveness of any Information System very much depends upon the organization of data files in a data bank, and the procedures adopted for data management In this chapter basics of data management will be covered. E Conventional Approach for Data Management Conventionally, for each transaction processing application, separate databanks are created, and the data is stored as sequential files, thus making the process of data updating and retrieval very slow. Further, the following problems are also associated with conventional way of storing the data files: 1. Data Redundancy: Since, each application has its own data files, the other users within the department / organization can not have access to these data files. Thus for every application separate data files are maintained, even if they are common. This causes data redundancy, and wastage of storage space. 2. Data Inconsistency: Data redundancy leads to data inconsistency. Data inconsistency means discrepancy in values of data elements in same data files physically stored at different locations. 3. Data Isolation: The data files of common use, can not be made available for sharing, even if desired so. 4. Security: There can not be enforcement of centralized control on data access, as the data files are created / duplicated as per individual applications requirements. The decisions regarding storing the same data at multiple places are taken at various levels by different people, which are usually of ad hoc nature. Access controls planning becomes difficult in such situation. 5. Data Dependency : The coding in applications is very much dependent upon the data files design. Any change in design of data files (say addition of a new field, or deletion of a field) will warrant for changes to be made in the coding of application also, which uses it.. 2 Training Division, NIC, New Delhi

3 6. Lack of enforcement of standards: It is very difficult to enforce standards in data files designs, as centralized view of data files is never available. E Database Approach The Database technology allows logical grouping ( the way, the user wants to view it, as per specific needs of an application) of data files associated with different applications in such a way, that the above mentioned problems associated with conventional way of data management are minimized. A database can be defined as follows: Database is a databank, which is managed by a single agency, and it consists of inter-related files, in which data items are organized in such a way that one can have random access to data, as per specific needs of the users. Important terms associated with a database are: Field: It is the smallest unit of data, which can be stored in a database. For example, a student s name in a university s database would appear in the field named as student_name. Usually the data types in a filed are Numeric, Character string, Date, Memo, Logical, Hyperlink, Picture etc. The field is at times referred as attribute/data element / data item also. These nomenclatures can be used synonymously. Record: It is a collection of related stored fields. A student record may consist of collection of fields like Student s name, the course taken, the date of birth, contact address and the grade etc. File (Table): It is a collection of different occurrences of same type of stored record. A file is usually referred as a Table also, it describes an entity (something, about which data is to be stored). Training Division, NIC, New Delhi 3

4 Database: A logical grouping of related files would constitute a database. For example, A Student file in a database may be linked to another file say Library books issue, which keeps record of books issues to students. The two files can be linked together by a common field say Student code, which will get reflected in Student file, as well as Library books issue file. Primary Key: Every record in a file usually contains at least one field that uniquely identifies that record for the purpose of data retrieval, and updating of values of fields corresponding to a record. This identifier field is called the primary key, and it always has a unique value. Combination of more that one fields to act as identifier of a record is called Composite Primary Key. Foreign Key: For setting relationship between two tables, there should be at least one common field in two tables. Usually that common field is Primary key in one table, and it is called Foreign key in the second table. Foreign key can have repeated values also. E ö Types of Data Model (based on logical 1 data structuring) Three types of common Data Models 1. Hierarchical: The hierarchical database model rigidly structures data into an inverted tree in which each record contains two elements. The first is a single root or master field, often called a key, which identifies the type location or ordering of the record. The second is a variable number of subordinate fields, which define the rest of the data within a record. 2. Network: The network database model creates relationships among data through a linked-list structure in which subordinate records (called members) can be linked to more than one data elements (called an owner). 1 The way user wants to view it as per specific needs of the application 4 Training Division, NIC, New Delhi

5 3. Relational: The relational database model is based on the simple concept of flat tables consisting of rows and columns. In this model, a table is equivalent to a file, row is equivalent to a record, and each column is equivalent to a field. Relations between different tables can be set through common fields. ö Comparison between the Three Models Model Advantages Disadvantages Hierarchical database Searching is fast and efficient. Access to data is predefined by exclusively hierarchical relationships, predetermined by administrator. Limited search/ query flexibility. Not all data is naturally hierarchical. Network database Relational database Many more relationships between data elements can be defined. There is greater speed and efficiency than relational database models. Conceptual simplicity is its characteristic. There is no predefined relationships among data. High flexibility in ad hoc querying. New data and records can be added easily. This is the most complicated model to design, implement, and maintain. It has greater query flexibility than hierarchical model, but less than relational model. Processing efficiency and speed is lower. Data redundancy can not be eliminated completely. Training Division, NIC, New Delhi 5

6 ö Emerging Data Models 1. Relational Multidimensional Database: Used for building Data warehouse. 2. Object-Oriented: Consists of inter-related objects, similar to entities consisting of attributes, methods associated with the object, and its behavior). 3. Hypermedia: Stores chunks information in the form of nodes, for which links are established by the user, as per specific needs. 4. Geographical Information Database: Used for managing locational data for overlaying on maps and images. 5. Knowledge Database: Consists of decision rules used to evaluate situations and help users to take decisions like an expert. E Types of Database Architecture (based on physical locations of the data files and data processing) 1. Centralized: A centralized database has all the related files in one physical location. Even the processing of data is done at the centralized location. Users can have access to the database application from remote computers / terminals. 2. Stand alone: A stand alone database has all the related files and the procedures for processing the data at one physical location only. Others can not have access to the database application. 3. Distributed: Database has complete copies of a database, or portions of a database, in more than one location. In this type of setup, even the processes associated with data management are distributed in various computers over network, usually close to the user. 6 Training Division, NIC, New Delhi

7 There are two types of distributed databases: Replicated: A replicated database has complete copies of the entire database in more than one locations, primarily to alleviate the single-point-of-failure problems of a centralized database as well as to increase user access responsiveness. Partitioned: Database is subdivided, so that each location has a portion of the entire database. The divided portions of database are locally maintained and are made available to others also for retrieval and further processing etc. Client-Server: The present trend is to build Client / Server based databases, in which common use data is stored on the server computer, and local requirement data is stored on client systems. Usually, the processes at client machine, request server to provide required data. The processes at server end make the required data available at client computer for further processing. This is a typical example of distributed database. In a nutshell, database technology allows an organizational data to be processed as an integrated whole. It reduces artificiality imposed by separate files for separate applications and permits users to access data more naturally. Now let us look into the procedures associated with Database Management and the tools available to do so. Training Division, NIC, New Delhi 7

8 E ö Database Management System Introduction Between the physical database (i.e. the data actually stored on a physical media) and the users( people, who access or update data), there is a need to follow standard procedures for data manipulation (additions/deletions/updations) & data retrieval. The database application developers should be able to integrate these procedures with their application procedures, as per their specific needs. A set of such procedures is called Database Management System (DBMS). In computer terminology, DBMS is defined as a software tool, used by computers to achieve the orderly storage of data, its processing and retrieval. ö Major Functions of DBMS 1. Creation / modifications / deletion of tables, which may be physically located at one computer or different networked computers 2. Manipulation of records in tables by sorting / filtering them 3. Searching of desired records & updating / deleting them 4. Mathematical / logical operations on the values in the fields 5. Facilitates design of user interface to link and automate various modules of application 6. Processing of user queries and presentation of results in tabulated form or predesigned reports form ö Components of DBMS 1. Data Model: It defines the way, the database is conceptually designed for setting relationship between fields, records and files. 8 Training Division, NIC, New Delhi

9 2. Data Definition Language (DDL): It defines the structure of database, and the way how, each data item appears in the database. DDL provides link between logical and physical views of the database. 3. Data Manipulation Language (DML): Data Manipulation Language of DBMS has the capability to write procedures for automating various DBMS functions as mentioned above, as per user/application requirements. It can be used with any other application language (3 rd generation/4 th generation) also. 4. Structured Query Language( SQL): It is the most popular Relational Database language, which allows the user to request for required information in most natural way. It actually combines both DML & DDL features of DBMS. The syntax of SQL commands is independent of Relational database brand. 5. Data Dictionary: It stores definitions of data fields, their standard names, aliases, associated business functions, data ownership details etc. Data Dictionary helps in maintaining data consistency, enforcement of standards, avoid duplicacy. It also enables independence of applications design from database design. ö Commonly used Relational Database Management Systems Name of DBMS MS Access Oracle SQL Server UNIFY Visual Foxpro Database Architecture Stand alone / Distributed Architecture based (as Client systems only) Mainly Client Server / Centralized Architecture based; Stand alone PC version also is available Client Server / Centralized Architecture based Client Server / Centralized Architecture based Client Server / Centralized Architecture based Training Division, NIC, New Delhi 9

10 ö Database Systems: Advantages in a Nutshell 1. Better planning of corporate database 2. Enforcement of standards 3. Transparency 4. Better control of data by providing appropriate access controls 5. Problems like redundancy / inconsistency can be minimized 6. Easy enhancement of database is possible without disturbing the existing working applications. 7. Improved security 8. Enhanced data integrity 9. Reduced application development and maintenance costs 10. Better / Automated backup and recovery procedures E ö Getting Started with Database Design Conceptual Design To begin with, one needs to be clear about the Information System requirements, for which database and the procedures are to be designed. This can be done by adopting systematic technique 2 for structured analysis. The output of this process is known as System Requirements Specifications (SRS). It mainly consists of: 1. A well defined objective of database application 2. List of agencies who supply inputs 3. List of agencies / roles who receive reports 4. List of expected output reports and their layout 5. List of inputs transactions & data entry forms layout 2 Detailed explanation of this technique is beyond the scope of this document. 10 Training Division, NIC, New Delhi

11 6. List of major processes 7. Layout of User Interfaces to link various processes 8. List of entities (something that can be identified in the user s work environment and whose data should be stored in the database) 9. List of properties / attributes associated with the entities 10. Conceptual database design including the logical view of data files along with associated data elements In this section, conceptual database design only will be discussed. The conceptual database design is independent of type of type of DBMS. It is done in two stages as follows: 1. Entity Relationship Diagram The Entity Relationship (E-R) Diagram of a database is a model of the database from the user or business perspective. It identifies various entities about which data needs to be stored, and also the relationships between those entities. For example, in Library Information System, we should have two entities about which data needs to be stored in the database. These are students and the books. Since, a student can get issued more than one books at a time, and a book can be issued to many students at different issue dates, the relationship between the two entities will be represented as follows: Student M Gets issued M Books Training Division, NIC, New Delhi 11

12 2. Normalization: The next step is to list out various attributes of the entities and their relationships. There will be some common attributes, and some dependent attributes. These attributes ( which can be referred as data elements also) are analyzed to minimize redundancy, and maximize integrity. This process of analysis is called Normalization. After the normalization process, various tables are identified, which constitute record structure with grouped data elements. The identified tables are linked through common data elements. These common data elements are defined as Primary key / Foreign Key / Composite primary key. In our example of Library Information System, the following tables will be identified as an output of conceptual design. 1. Student table consisting of fields, Student-code, Student-name, Class, Date of birth, postal, address, phone no, etc. Here Student-code is primary key which is unique 2. Books table consisting of fields, Book-code, Book name, Author, cost, edition, Accession no. etc.. Here book-code is primary key, which is unique 3. Issue table consisting of fields, Student-code, Book-code, Issue-date, status Here Student-code+Book-code+ Issue-date is composite Primary key, which is unique. Student-code and Book-code are foreign keys, and can have duplicate values. 12 Training Division, NIC, New Delhi

13 Graphical Illustration: Student Table Student- Code Student- Student Class Date of birth Address - address Code Name 1 Shayam 1 st 11/05/ , 2 nd Street, [email protected] Year Janpath, New Delhi 2 Ashish 2 nd 21/07/84 11, Sector 7, [email protected] Year Vikas Puri, New Delhi Issue Table Book-Code Issue-date Status /10/ /08/2002 Returned /08/2002 Books Table Book-code Book Name Author Edition Cost 1 Visual Basic I.K. Jain MS Access-An R.P. Singh Overview Training Division, NIC, New Delhi 13

14 ö Physical Design In the physical design, the actual structures of tables are created using a particular DBMS package. The physical design shows how the files, records, fields are actually stored on the physical storage media, depending upon the type of database, the DBMS supports. This physical design giving complete logical view ( the way user wants to view it) of the database, is called schema. Various applications developers have the choice of getting different logical views (which may be even partial) of the same database. They can customize these views as per their specific needs. Such logical view is called subschema. DBMS provides tools for creating the subschemas. This characteristic of DBMS makes the database design independent of applications design. That means, any changes made in the database design will not affect already working applications, unless the data elements, being used by them are deleted from the database. 14 Training Division, NIC, New Delhi

15 E Getting Started with MS-Access MS Access is a Relational DBMS, for windows based desktop database applications, which may be stand alone or distributed over network. In a Client-Server environment, it is used to maintain database at the client end. Database in MS Access is referred as a collection of data, procedures, reports, interfaces etc. related to a particular purpose. It has mainly the following components. Tables to contain data in the form of records / fields. Forms to manipulate data and user interfaces to link forms, sub forms or processes. Queries to create logical view of data and also to find and retrieve desired data based on various conditions. Reports to print information in pre-laid formats Pages to publish the reports / queries output on Web Macros to club more that one operations and automate their executions Modules to add more functionality by writing codes using Visual Basic for Applications (VBA), which is scripting language integrated with MS Access. It is similar to Visual Basic. Training Division, NIC, New Delhi 15

16 q Case Study 1. Name of Database application : Employees Leave Record System (ELRS) 2. Broad objective of the application: To keep the information of employees and details of leave taken by them during the service. The system should also update the balance leave at the end of calendar year, by adding leave due in the coming year. 3. Brief description of the application This application is designed for Leave account maintenance of the employees of an organization. Year end processing to add Earned leave and initialize Casual Leave balance. 4. List of various reports expected to be generated Employee s details report Detailed leave report of an individual employee, along with leave at balance 5. List of various input forms Addition of data of new employees Updating of Employee s information Deletion of employees, who leave the organization Data entry of leave taken by an employee from time to time 6. List of major processes Maintenance of data of Employee (Additions/Deletions/Modifications) Maintenance of record of leave details Year end processing 16 Training Division, NIC, New Delhi

17 7. List of entities identified ( about which the data is to be stored ) Employee details Leave details 8. List of data items associated with above entities Employee: Leave details: Name, Designation, Date of Joining, Skill, address, employee photograph etc. Name of the employee, Designation, Leave type, Duration, Start Date, End Date, balance leave at credit. 9. Entity - Relationship Diagram ( Conceptual Design of database) Employee Takes Leave 10. After Normalization process, we will get the conceptual design in the form of the following two tables. Employee table consisting of fields: Employee-code, Name, Designation, Date of Joining, Skill, EL at credit, CL at credit, RH at credit, HPL at credit, Salary, address, employee photograph etc. Here Employee-code is the Primary Key. Training Division, NIC, New Delhi 17

18 Leave table consisting of fields: Employee-code, Leave type, Duration, Start-Date, End Date Here Employee-code + Start-Date is a Composite Key, and Employee-Code is Foreign Key. 11. User Interfaces Design Maintain Employees data Enter Leave Details Year End Processing Reports / Queries Reports Page Employee Report Creating Employee Label Leave Details of Individual employee Maintain Employee Data Add New Employee Modify Employee Data Delete Employee Data Enter Leave Details Form for entry of multiple leave details of an employee 18 Training Division, NIC, New Delhi

19 Few suggested enhancements to the above mentioned case study, which can be done by participants as assignment. Add login screen for screen for maintaining employee data to enforce Access controls. Calculate gross pay of employees and generate pay slips by automatically calculating DA from the basic salary. Add a filed in Leave table to set hyperlink to leave sanction order (MS Word file). Generate MS Word document for leave details statement for every employee with a provision to send it as an attachment to of that employee (You cal use Mail merge option). Publish employees list on Web along with their leave at credit. Create a new table containing department code, and other details. In employee table, add a field for department, to which employee belongs. In the properties of this field, pickup the values for department field from the department table through lookup Wizard. Develop a module for periodic backup of tables. This process should get triggered, on mouse click on the main menu. Develop a module for automatic backup of tables. This process should get triggered, automatically on 1 st day of every month. On the similar lines of the case study, you can also develop a database application relevant to your work area. Training Division, NIC, New Delhi 19

20 q Starting MS Access Switch on the system. In case login dialog box appears, enter user name and password as User (Cabin No) (For example, for Cabin 42, user name and password will be user42). Click Start>>Programs>>MS Access. Dialog box shown in Figure 1 will appear. Select this for blank database option. Figure 1 Select Blank Access database option. The dialog box shown in Figure 2 will appear. 20 Training Division, NIC, New Delhi

21 Figure 2 Select the folder name in Save in option. Type Employee under File name. Click Create. Employee database window will open as shown in Figure 3. To open table for data entry To make modification in design of table Figure 3 To create new table Training Division, NIC, New Delhi 21

22 After the database has been created, different objects of the database like Tables, Queries, Forms, Reports etc. can be created by selecting appropriate tabs. Note: We are going to refer to this database window in later part of the workbook also. E ö Ways of Creating a Table Create table in design view In this option, table has to be created from scratch, in which its fields names, their data types and properties have to be entered. ö Create Table by using Wizard In this option, wizard dialog box will open with the steps provided to create a table. ö Create table by entering data In this option, only data has to be entered and it will take fields names as field1, field2 and so on and data type it will take automatically based upon data entered (one can rename the fields names, if required). E Creating New Table Double click Create table in Design View. Note: Another way to get Design view for new table, Click New>>Design View>>OK. New Table dialog box will appear as shown in Figure Training Division, NIC, New Delhi

23 Figure 4 As shown in Figure 5, enter names of fields in Field Name column, type of data to be entered in fields in Data Type column and enter description of fields in Description column if required. Figure 5 Training Division, NIC, New Delhi 23

24 E Saving the Table Click File>>Save. The dialog box as shown in Figure 6 will appear. Figure 6 Type the Table name as Employee and click OK. The dialog box as shown in Figure 7 will appear. Figure 7 E Select No. Table will be saved with the name Employee. Close the table Employee. Adding Records to a Table Select table Employee from database window. Click Open.Datasheet View of the table will open as shown in Figure Training Division, NIC, New Delhi

25 Figure 8 Start entering the data from the cursor placed at the first blank record. The following data may be entered as shown in Figure 9. Save and Close the table window. Figure 9 E Deleting Records Click on the record to be deleted. Select Edit>>Select Record. The record gets selected as shown in Figure 10. Figure 10 Training Division, NIC, New Delhi 25

26 Click Edit>>Delete Record from the menu bar, the record will be deleted. Note : To delete all record, click Edit>>Select All and press Delete button. But don t try this option otherwise you will lose whole data of that table. E ö ö Editing Data in Tables Cutting & Pasting Or Copying & Pasting Data Select the record to be cut or copied. Select Edit >> Cut (for cutting data) or Edit>>Copy (for copying data). Take the cursor to a new position in the table where the record is to be copied. Select Edit>>Paste. Locating Data Select the field where the data has to be searched, by clicking the Field Heading OR put the cursor anywhere in the column where the data has to be searched. Click Edit>>Find. The Find and Replace dialog box appears as shown in Figure 11. Click here to select the field. Figure Training Division, NIC, New Delhi

27 ö Enter a string to search for, in the Find What: option, say ANIL. In Match option, select any of the three category provided. Choose Find Next to search for more records. Select Cancel to stop the search and close the dialog box. Replacing the existing data Click on the field name where the data is to be replaced. For example, click on Designation field Select Edit>>Replace. The Replace dialog box as shown in Figure 12 will appear. Figure 12 Type SA in Find What field. Click on the Replace With field. Type SSA. Click on Find Next button. It will find the first occurrence of the data. Click on Replace to replace the data in that field. Click on Find Next to find and then click Replace to replace the next occurrence of the data (If required, click Replace All to replace all such occurrences). Close the Find and Replace dialog box by clicking the Close button. Training Division, NIC, New Delhi 27

28 E Sorting Data Data stored in a table can be sorted on text, numbers, or date fields in ascending order (A to Z, zero to 9, or earliest to latest date). Or, you can sort in descending order (Z to A, 9 to zero, or latest to earliest date). Click on the Field on which the records are to be sorted. Click Records>>Sort>> Sort Ascending from the Record menu option. The option provides you to rearrange the records Ascending/Descending on Name field as shown in Figure 13. Figure 13 E Close the table window Click Yes, if changes are to be saved in the table. Modifying Table Design Select the table to be modified from the database window. Select Design. The table will open in Design View. The design of the fields in table can now be modified, i.e., the fields can be deleted, added or changed according to the requirements. After the modification, changes can be saved and the database window reappears. 28 Training Division, NIC, New Delhi

29 E Primary Key A Primary Key is a field (or group of fields) that uniquely identifies each record. When primary key is created, Access will do the following things: 1. Make sure no two records in the table have the same value in the field (or group of fields) that defines the primary key. 2. Keep records sorted (ordered) by the entries in the primary key. 3. Speed up processing. Note: No field that is part of a primary key can be left blank during data entry. ö Setting a Primary Key Open the table in Design view. Select the field for which primary key property has to be set. Click Edit>>Primary Key. The field which is set as the primary key, will have key icon in the row selector as shown in Figure 14. key icon row selector Figure 14 Note: If the data in a table contains duplicate data for the emp_code field, the error message will be displayed while defining the emp_code field as a primary key. To remove the error, first remove the duplicate data and then define field as a primary key. Training Division, NIC, New Delhi 29

30 ö E Removing Primary Key Setting Select the field for which primary key setting has to be removed. Click Edit>>Primary Key. It will remove primary key setting. Creating Second Table Let us now create another table Leave with the following fields: Emp_code Type_Leave Start_Date Duration End_Date Number Text Date Number Date Save this table as LEAVE table. Close the table design window and enter the data for this table. It may be noted that the values of Emp-code should be the same as those already mentioned in the Employee table. 30 Training Division, NIC, New Delhi

31 q Relationships In RDBMS systems, usually data is stored in more than one table, depending on the type of information. To bring the relevant information together in a Form/Report/Query, these tables need to be linked together. To link the tables together Relationships are used. For example, there are two tables Employee table, which contains employees details, and other Leave table, which contains the information about the leaves taken by all the employees. To create a report, which will give the details of the leaves taken by all the employees, relationship between the two tables Employee and Leave is required. Sample report having data from both the tables is shown in Figure 15. E How it works? Figure 15 In the above example, the fields in both tables must be linked so that they show relevant information about the employees. This linking is done by setting relationships between tables. A relationship is created by matching data in one of the fields of the table usually a field with the same name in both tables. In most cases, these matching fields Training Division, NIC, New Delhi 31

32 are the primary key 3 from one table and a foreign key 4 in the other table. For example, employees can be associated with the leaves they have taken by creating a relationship between the Employee table and the Leave table using the Emp_code (Employee Code) field as shown in Figure 16. Primary Key Employee Table Foreign Key Leave Table Figure 16 Entity-Relationship diagram Employee Table s Emp_code Takes Leave Leave Table s Emp_code 3 Primary key consists of one or more fields (columns) whose value or values uniquely identify each record in a table. A primary key cannot allow Null values and is used to relate the table to foreign keys in other tables. 4 Foreign key is one or more table fields (columns) that refer to the primary key field or fields in another table. A foreign key indicates how the tables are related. The data in the foreign key and primary key fields must match, though the field names do not have to be the same. 32 Training Division, NIC, New Delhi

33 Types of Relationship 1. A one-to-many relationship : It is the most common type of relationship. In a one-to-many relationship, a record in the first table can have many matching records in the second table, but a record in the second table has only one matching record in the first table. 2. A many-to-many relationship In a many-to-many relationship, a record in the first table can have many matching records in the second table, and a record in the second table can have many matching records in the first table. This type of relationship is only possible by defining a third table (called a junction table) whose primary key consists of two fields the foreign keys from both the tables, first and second. A many-to-many relationship is actually defining two one-to-many relationships with a third table. For example, the Leave table and the Training table have a many-to-many relationship that s defined by creating two, one-to-many relationships to the Employee table. 3. A one-to-one relationship In a one-to-one relationship, each record in the first table can have only one matching record in the second table, and each record in the second table can have only one matching record in the first table. This type of relationship is not common, because most of the information related in this way would be in one table. You might use a one-to-one relationship to divide a table with many fields, to isolate part of a table for security reasons, or to store information that applies only to a subset of the main table. E Creating New Relationships Close any tables you have opened since relationships can t be created or modified between open tables. Click Tools>>Relationships. Blank screen will appear. Training Division, NIC, New Delhi 33

34 Click Relationships>>Show Table. Following Show Table dialog box will appear as shown in Figure 17. Figure 17 Select Employee table. Click Add. Select Leave table. Click Add. Similarly you can add more tables depending upon the requirement. Click Close. Tables selected will appear as shown in Figure Figure 18 Drag the Emp_code of Employee table over Emp_code of Leave table to relate them. Edit Relationships dialog box will appear as shown in Figure 19. Training Division, NIC, New Delhi

35 Figure 19 Click Create. A line joining the two tables will appear as shown in Figure 20. Figure 20 The above two steps can be repeated for each pair of tables you want to relate. Close the Relationships window. The system will prompt for the Saving of Relationship. Click Yes. Note: If you drag a field that isn t a primary key and doesn t have a unique index to another field that isn t a primary key and doesn t have a unique index, an indeterminate relationship is created. Training Division, NIC, New Delhi 35

36 E Editing the Existing Relationship Click Tools>>Relationships. Double click on the middle of the relationship line. Edit Relationship dialog box will appear as shown in Figure 21. Figure 21 ö Defining the join type for a relationship between two tables Click the Join Type. button, and then click the desired join type from the Join Properties dialog box as shown in Figure Training Division, NIC, New Delhi

37 Figure 22 ö ö Click OK. Deleting Relationship Click Tools>>Relationships. Click on the Relationship line to be deleted. Press Delete key. Removing Table from the Relationship Window Click Tools>>Relationships. Click on the table to be deleted. Press Delete key. Training Division, NIC, New Delhi 37

38 Referential Integrity Referential integrity is a system of rules that Microsoft Access uses to ensure that relationships between records in related tables are valid, and that you don t accidentally delete or change related data. Basic requirement for setting up referential integrity: 1. The matching field from the primary table is a primary key or has a unique index. 2. The related fields have the same data type. 3. Both tables belong to the same Microsoft Access database. When referential integrity is enforced, you must observe the following rules: 1. You can t enter a value in the foreign key field of the related table that doesn t exist in the primary key of the primary table. 2. You can t delete a record from a primary table if matching records exist in a related table. For example, you can t delete an employee record from the Employees table if there are leave details for that employee in the Leave Table. If at all it is required to delete a record in Employee table, one should just delete the corresponding leave details from the Leave table. 3. You can t change a primary key value in the primary table, if that record has related records. Setting Referential Integrity Open the relationship in edit mode as already discussed in Editing the Existing Relationship section. Select the Enforce Referential Integrity check box. If referential integrity is enforced and you break one of the rules with related tables, Microsoft Access displays a message and doesn t allow the change. Restrictions can be overridden against deleting or changing related records and preserving referential integrity by setting the Cascade Update Related Fields 5 and Cascade Delete Related Records 6 check boxes. 5 Changing a primary key value in the primary table automatically updates the matching value in all related records. 6 Deleting a record in the primary table deletes any related records in the related table. 38 Training Division, NIC, New Delhi

39 q Query A query is logical view of selected data elements from tables as per the specific needs of the user (which is called subschema). Query option is used for the purpose of display, updating or analysis of data. E Simple Query Select Queries tab from the database window. Click on New button as shown in Figure 3 of table design. The dialog box for new query will appear as shown in Figure 23. Figure 23 Select Design View. Click on OK. The Show Table dialog box lets you select the tables/queries/both for creating a query. Select the table Employee. Click on Add. The field list appears next to the Show Table dialog box as shown in Figure 24. Training Division, NIC, New Delhi 39

40 Figure 24 In Show Table dialog box, click on Close button. Double Click on fields Emp_code, ename, Designation, Salary in the field list. They may appear in the lower part of the screen as shown in Figure 25. Figure 25 Save the query as Employee_query. Select Query>>Run from the menu bar to see the output. Close the Select Query window. Note: From the database window also the query can be run. Click on Queries tab, choose the query as Employee_query and click on Open button. 40 Training Division, NIC, New Delhi

41 E Performing Calculation in the Query A new field can be created in a query that displays the results of a calculation defined in field cell with an expression. Open the query in Design view. Repeat all the steps as done in previous query. Type an expression in an empty cell in the Field row as shown in Figure 26. In this figure the expression written is DA:[Salary]*0.42 Figure 26 Expression to calculate DA Note: For creating the expression, Expression Builder can be used. Right-click in the Field cell where you have to add the calculated field, and then click Build. Select Query>>Run to see the output. The calculated value for DA, with the field name DA, will be displayed in the output of query. Close the Query window. Training Division, NIC, New Delhi 41

42 E Using Criteria or Advanced Filters to retrieve certain Records Criteria are restrictions or an advanced filter placed on a query to identify the specific records to work with. For example, instead of viewing all the employee information of your organisation, selected employees can be viewed having Designation SA. To do this, specify the criteria that limits the results to records whose Designation field has the value SA. In a design grid of query, enter an expression in the criteria cell for the field. The expression in the preceding example would be SA as shown in Figure 27. Note : Additional criteria can be entered for the same field or different fields using either the And or the Or operator. For And operator, the expressions are in different cells in the same row. For Or operator, the expressions are in different rows of the design grid. Figure 27 Select Query>>Run. The output contains only those records having Designation equal to SA. 42 Training Division, NIC, New Delhi

43 E Parameter Queries A parameter query is a query that while running displays its own dialog box prompting you for information, such as criteria for retrieving records or a value you want to insert in a field. You can design the query to prompt you for more than one piece of information; for example, you can design it to prompt you for two dates. Microsoft Access can then retrieve all records that fall between those two dates. In query Design view, drag the fields from the field list to the query design grid. In the Criteria cell for the field you want to use as a parameter, type a prompt enclosed in square brackets as shown in Figure 28. Figure 28 The prompt Type Employee Code will be displayed when you run the query as shown in Figure 29. Figure 29 Enter the value for employee code and click OK. It will display the output having emp_code, name, designation, salary and DA for the corresponding employee code. Training Division, NIC, New Delhi 43

44 E Action Queries An action query is a query that makes changes to many records in just one operation. The action queries are of four types: delete, update, make-table, and append queries ö Delete Query Delete Query deletes a group of records from one or more tables. With delete queries, always entire records will be deleted, not just selected fields within records. Single delete query is used to delete records from a single table or from multiple tables, if relation has been set between the tables, in a one-to-one relationship or a one-to-many relationship. Select Query>>New>>Design View from Database dialog box. Add tables Employee and click the Close button. Select Query>>Delete Query, from the Menu bar. Drag the asterisk(*) from the field list for the table, from which records are to be deleted, to the query design grid. From appears in the Delete cell under this field. Add field and table to the design grid for which criteria for deleting records has to be specified. Where appears in the Delete cell under this field. In the Criteria cell for the fields, criteria has to be typed as shown in the Figure Training Division, NIC, New Delhi

45 Figure 30 Note: If Delete Query is used for One-to-many relations, records will be deleted from all the related tables. For example, tables Employee and Leave are having oneto-many relationship (select the Cascade delete related records option while setting the relationship.) In this case, the Delete Query will delete the records from both the tables related, if the Salary is less than To see a list of the records going to be deleted, click View >>Datasheet view. To return to query Design view, click View >>Design View. Click Query>>Run to delete the records permanently from the tables. Training Division, NIC, New Delhi 45

46 ö Update Query Change records as a group using an update query Create an update query, selecting the tables or queries that include the records you want to update and the fields you want to use for setting criteria. In query Design view, click the Query>>Update Query. Drag from the field list to the query design grid the fields you want to update or you want to specify criteria for. In the Criteria cell, specify the criteria if necessary. In the Update To cell for the fields you want to update, type the expression or value you want to use to change the fields, as shown in Figure 31. Figure 31 To see a list of the records that will be updated, click View >>Datasheet View. This list won t show the new values. To return to query Design view, click View >> Design View. Click Query>>Run to make the table updated. 46 Training Division, NIC, New Delhi

47 Update a table based on values in another table Create an update query that contains the table you want to update and the table whose values you want to copy. If the tables aren t already joined, join them on the fields that have related information. For example, if you want to copy data from the Name field of the Employee table to a field in Leave table, join the two tables on the primary key, which in this case is Emp_code. In the Update To cell for the fields you want to update, type an expression with the following syntax: [tablename].[fieldname], where tablename and fieldname are the names of the table and field that contain the data you re copying. For example, if you are copying data from the Name field of the Employee table, you would type [Employee].[Name] in the Update To cell as shown in Figure 32. Figure 32 Click Query>>Run. It will copy the data from Name field of Employee table to the Name field of the Leave table. (To see the updated table, you may see the Leave table in Datasheet view). Training Division, NIC, New Delhi 47

48 ö Make-table Query Create a query, selecting the tables or queries that contain the records you want to put in the new table. In query Design view, click Query >> Make-Table query. The Make Table dialog box appears. In the Table Name box, enter the name of the table you want to create or replace. For example, to create new table employee_new, type that name in the Table Name box. Click Current Database to put the new table in the currently open database. Or click Another Database if you want to create table in a new database and type the name of the database you want to put the new table in. Type the path if necessary. Click OK. Drag from the field list to the query design grid the fields you want in the new table. In the Criteria cell for the fields that you ve dragged to the grid, type the criteria as shown in Figure 33. Figure Training Division, NIC, New Delhi

49 ö For the preview the new table before you actually create it, click the View>> datasheet view. Return to query Design view by clicking View>>Design View. To create a new table, click Query>>Run. It will copy all the fields shown in Figure 33 and its data to the newly created table employee_new. Append Query This query is used to append records from one table to another table using an append query. Create a query that contains the table whose records you want to append to another table (can be done using Simple Query Wizard option). Open the query created in the above step in design mode. Click Query>>Append Query. The Append dialog box appears as shown in Figure 34. Figure 34 In the Table Name box, enter the name of the table you want to append records to. Click Current Database if the table is in the currently open database. Or click Another Database and type the name of the database where the table is stored. Type the path if necessary. Click OK. Training Division, NIC, New Delhi 49

50 In Append To option, select the Field name of the table where the data has to be appended and in Criteria cell for appending the field value as shown in Figure 35. Figure 35 If all the fields in both tables have the same names, you can just drag the asterisk (*) to the query design grid. However, if you re working in a database replica, you ll need to add all the fields instead. If the fields you ve selected have the same name in both tables, Microsoft Access automatically fills the matching name in the Append To row. If the fields in the two tables don t have the same name, in the Append To row, enter the names of the fields in the table you re appending to. In the Criteria cell for the fields that you have dragged to the grid, type the criteria on which additions will be made. Click Query>>Run to execute the query. Note : So far, the practice for basics of Queries has been done. For further details, you may continue through the following pages, else go to the Section on Forms on Page Training Division, NIC, New Delhi

51 E ö More about Queries Cross-tab Query Cross-tab queries let you cross-tabulate data in a row-by-column fashion. The example shown below answers the question Who took how many leaves of what type?. Note : To quickly create Cross-tab query of data in a single table, Crosstab query Wizard can be used. Click New>>Design View>>OK. Click Query>>Cross-tab query. Add table Leave to be worked upon as shown in Figure 36. Figure 36 In the design grid of query, specify which field s values become column headings, which field s values become row headings, and the summary values and how you want to summarize the value (for example, sum, average, count, or otherwise calculate). Steps for creating Cross-tab query are as follows: Choose Row Heading in the Crosstab cell for the field you want to use for row heading. More than one field can be designated, but at least one field must be Group By in its Total Cell as shown in Figure 37. Expressions can also be used to group the value together. Training Division, NIC, New Delhi 51

52 Choose Column Heading in the Crosstab cell for the field you want to use for column heading. Only one field is allowed and it must contain Group By in its Total Cell as shown in Figure 37. Expressions can also be used to group the value together. Choose the summary value in the Crosstab cell for the field you want to summarise. In the Total Cell, choose the summary (usually it is Sum or Average). Don t choose Group By for this field. Other fields can also be chosen in Crosstab cell, you want to group by, without displaying them in result. Click View>>Datasheet View to view the result. For the setting in design grid of query, result is shown in Figure 37. These settings will display the field s value as Row headings These settings will Display the field s value as a Column heading. These settings display the total of leaves. Figure Training Division, NIC, New Delhi

53 ö SQL specific Query An SQL query is a query that is created using an SQL statement. Examples of SQLspecific queries are: Union Query This type of query combines fields (columns) from one or more tables or queries into one field or column in the query s results. For example, NIC Cell in ministries have to give the attendance report of its staff each month to NIC HQ. These lists from all ministries can be combined into one result set using a union query, and then create a make-table query based on the union query to make a new table. For example NIC HQ is getting the attendance list from two ministries Minis1 and Minis2. These two lists can be combined through union query. The two tables Minis1 and Minis2 are shown in Figure 38. Figure 38 For Union Query, select Queries >>New then click Design View>>OK. Add tables minis1 and minis2. Click on Query>>SQL Specific>>Union. Training Division, NIC, New Delhi 53

54 A Union Query window is opened. Type the SQL statement given below: SELECT [EMPCODE],[ATTENDENCE] FROM MINIS1 WHERE MONTH= JANUARY UNION SELECT [EMPCODE], [ATTENDENCE] FROM MINIS2 WHERE MONTH= JANUARY ; Click Query>>Run. The output will be as shown in Figure 39. Figure 39 Pass-through Query This type of query sends commands directly to ODBC databases, such as Microsoft SQL Server, using commands that are accepted by the server. For example, pass-through query can be used to retrieve records or change data. Data-definition Query This type of query creates or alters database objects, such as Microsoft Access or Microsoft SQL Server tables. 54 Training Division, NIC, New Delhi

55 Subquery This type of query consists of a SQL SELECT statement inside another select query or action query. These statements can be entered in the Field row of the query design grid to define a new field, or in the Criteria row to define criteria for a field. Add table Employee for this query and write the following SQL statement: SELECT Employee.EMP_CODE, Employee.NAME FROM Employee WHERE (((Employee.NAME)= Sushila )); Type Sushila in criteria row and in name column as shown in Figure 40. Figure 40 Click View>>Datasheet View. The output will be displayed having those records where NAME= Sushila. Note : If subquery is defined in a Field cell, type a SELECT statement enclosed in parentheses in a Field cell. To Zoom the field cell press Shift+F2. For example: Leave taken : (select [duration] from [ leave] where [employee].[emp_code]=[leave].[emp_code]) Training Division, NIC, New Delhi 55

56 Figure 41 In the example shown in Figure 41, two tables Employee and Leave are used with the relationship set on the field emp_code. In this Query, Emp_code and Name from Employee table and duration from Leave table is selected where the emp_code of both the tables are equal. Click Query>>Run. The output will be as shown in Figure 42. Figure 42 E Accessing Query through Form To access query through form, first create a form having the fields on which the criteria is to be set in the query and then create a button to run the query. For example, we want to display all the employees details having the same designation. To do this, first create Form having combo box and a button as shown in Figure Training Division, NIC, New Delhi

57 Figure 43 To do this, in a design mode of form Create combo box having all the Designation from the designation field of the table. Create a query, Query new having all the required fields to display and in Criteria cell of Designation field give criteria [forms]![form1]![combo1] Create Button and in Command button wizard, select category Miscellaneous and action Run Query. Here forms mean that a form is called. Form1 is the form name. Combo1 is the field from where value is taken for criteria. The design view of query is shown in Figure 44. Figure 44 Training Division, NIC, New Delhi 57

58 To get the output Run the form and enter the value for designation and click button Run Query. Output will be displayed as shown in Figure 45. Figure Training Division, NIC, New Delhi

59 q Forms A form is a graphical user interface, which can be customized as per user requirements and is used for the following purposes: Forms for data-entry in one or more than one table. User interface forms to set links to various actions to be performed on the application, for example, Switchboard. To create custom dialog box to accept user input, and then carry out an action based on that input. E Creating a Form using Wizard Select Forms tab from the database window. As in the case of tables and queries, for forms also there are three option buttons- Open, Design and New. To create a new form, click New>>Form wizard>>ok or Double Click on Create form by using wizard. The dialog box shown in Figure 46 appears. Figure 46 Training Division, NIC, New Delhi 59

60 Select the table Employee from the Table/Query 7 listbox. Select the fields to be displayed on the form. Click Next. Select the layout and style of the form in the next two steps. Type the title of the form as Employee and click Finish. The form will be opened in the Form View mode as shown in Figure 47. Figure 47 Close the form. Note : Modification in the form can be done in the Design view of the form. To go in design view of form, click View>>Design View. 7 A form can take the data from table or query for viewing and editing purpose. 60 Training Division, NIC, New Delhi

61 E Creating a Form in Design View In the Database window, click the Forms tab. Click New. In the New Form dialog box, click Design View. Select the name of the table or query that includes the data you want to base your form on. Note : If the form won t contain data (for example, if you want to create a form to use as a switchboard to open other forms or reports, or if you want to create a custom dialog box), don t select any Table or Query from this list. Click OK. Form will appear as shown in Figure 48. Figure 48 Select View>>Field List. This will give the field list as shown in Figure 49. The required fields can be dragged on to the form. Form will appear as shown in Figure 49. Save the form and give it a name, say, empform. Close the form. Training Division, NIC, New Delhi 61

62 Field List Figure 49 From the Database window, double click the empform you will be able to see different records from the form, as shown in Figure 50. Figure Training Division, NIC, New Delhi

63 E Different Controls In a form, we can also introduce many controls. Various controls (like label, textbox, combobox, command button, tab etc.) available on the tool bar as shown in Figure 51, can be put on the form. ö Label Figure 51 Label on a form or report is used to display descriptive text such as titles, captions, or brief instructions. Labels do not display values from fields or expressions; they re always unbound and they don t change as you move from record to record. Open a form in Design view Click the Label tool in the toolbox. On the form, click where you want to place the label, and drag the mouse. In the label drawn, type the text for the label. ö Text boxes Text boxes are drawn on a form or report to display data from a table, query, or SQL statement. This type of text box is called a bound text box because it s bound to data in a field. Text boxes can also be unbound 8. For example, you can create an unbound text box (i.e. text box isn t bound to the data in field) to display the results of a calculation, or to accept input from a user. 8 Data in an unbound text box isn t stored in field of table. Training Division, NIC, New Delhi 63

64 Create a bound Text box Open a form in Design view. Click View>>Field List. Drag the field(s) from the field list and position them on the form. Create an unbound Text box Click the Text Box Tool in the toolbox. Click anywhere on the form to create a default-sized text box, or drag to create a text box that s the size you want. Create a Text box for computed Fields (for numeric and text entries) Open a form in Design view and select a table from the New form dialog box Click the textbox tool in the toolbox. Click on the form where the control has to be placed and do the following:- Note: A text box is the most common type of control used to display a calculated value, but you can use any control that has a Control Source property. Type the expression in the Control Source property of the textbox. For example, for the calculation of DA, type expression = [salary] * 0.43 in the Text box. Note: To use the Expression Builder to create the expression, click View>>Properties to open the control s property sheet, and then type the expression in the Control Source property box or click the Build button to open the Expression Builder. ö Create a command button with a wizard Open a form in Design view. Click the Control Wizards tool in the toolbox if it s not already pressed in. In the toolbox, click the Command Button tool. On the form, click where you want to place the command button. The wizard dialog box will be opened as shown in Figure Training Division, NIC, New Delhi

65 Figure 52 Follow the directions in the wizard dialog boxes. In the last dialog box, click Finish to display the command button in Design view. You may introduce many buttons on the form like this. The view of buttons will appear as shown in Figure 53. Figure 53 Training Division, NIC, New Delhi 65

66 ö Create a List Box or combo box List box or combo box is quicker and easier way to select a value from a list than to remember a value to type. The list in a list box consists of rows of data. Rows can have one or more columns, which can appear with or without headings. If data type of field is Lookup field in table Create a Lookup field in table Design view by selecting Lookup Wizard as Data Type and follow the directions in the wizard dialog boxes and create a new form based on a that table. In form Design view, click view>>field List and then drag the Lookup field from the field list to the form. Microsoft Access automatically creates the lookup list box or combo box. OR If data type of field is not a Lookup field in table. Open the form in Design view. In the toolbox, click the ListBox or ComboxBox and then click on the form where these controls have to be placed and follow the directions in the Wizard dialog boxes. Switch to Form view to test the list box or combo box. It will appear as shown in Figure 54. Figure Training Division, NIC, New Delhi

67 ö To remove navigation bar from the view of form At the button of each form, we generally have a navigation bar which is used to display the record no. A navigation bar is shown in Figure 55. Figure 55 The steps to remove the navigation bar from the view of the form, are as follows: Open the form properties by right clicking the mouse button by placing the cursor at left most corner of the form in design view as indicated by arrow. It will appear as shown in Figure 56. Click here to open form property dialog box. Figure 56 In the form properties, select Navigation Button option to NO. The view of the form will appear without navigation bar at the bottom Training Division, NIC, New Delhi 67

68 ö Creating Subforms A subform is a form within a form. The primary form is called the main form, and the form within the form is called the subform. A form/subform combination is often referred to as a hierarchical form, a master/detail form, or a parent/child form. Subforms are especially effective when data has to be shown from tables or queries with a one-to-many relationship. Open the form in Design view in which subform has to be added. Make sure the Control Wizards tool in the toolbox is pressed in. Click the Subform tool in the toolbox and click on the form where the subform is to be placed. Follow the directions in the wizard dialog boxes. The view of the form will appear as shown in Figure 57. Figure 57 In this figure, a subform is created using table personalinfo having one to many relationships with the table Training. 68 Training Division, NIC, New Delhi

69 E ö Further Enhancements in Form Design Form with multiple pages using tabs Open a form in Design view. In the toolbox, click the Tab Control tool and then click on the form where the control has to be placed. Microsoft Access adds a tab control with two pages. The first page is on top. Click Field List on the toolbar to display the field list and drag one or more fields to the tab page by selecting option Page1 or Page2. Form will appear as shown in Figure 58. Figure 58 Note: To change the name of a Page tab, double-click the page (Page1 or Page2) to open its property sheet, and then specify a new name in the Caption property. If you don t specify a name in the Caption property, Microsoft Access uses the setting in the Name property. To add, delete, or change the order of tabs, click the border of the tab control with the right mouse button and click Insert Page, Delete Page, or Page Order. ö Adding pictures, graphs and sound to a Form To add a picture or chart to the form, select Insert>>Picture or Insert>>Chart. Choose the picture from the available ones or make one of your own. Select Insert>>Object to add Excel Sheet, Chart, bitmaps, presentation, etc. to the form. Training Division, NIC, New Delhi 69

70 ö Create a new object by selecting Create New or use the already existing object by selecting Create from File option. Check the Display As Icon option In the Object type dialog box, select Sound. Select OK. To view selected records through a form In a view of form or subform or datasheet, select the entire contents of that field on which filter s results is based. Select the value in form view or database view (as shown in figure, the Designation value SSA is selected for filter) and then click Filter By Selection on the toolbar. The output of the form will appear as shown in Figure 59. Figure Training Division, NIC, New Delhi

71 ö ö Adding page Numbers and Date Open the form in Design view. Click Insert >> Page Numbers or Insert >> Date And Time. In the Page Numbers dialog box, select the format, position, and alignment for the page number. To include a date, select the Include Date check box, and then click a date format. To create a hyperlink in the form Hyperlinks can be used in forms and datasheets to jump to objects in the same or another Microsoft Access database, to documents created with Microsoft Word, Microsoft Excel, and Microsoft PowerPoint, and to documents on the global Internet or on a local intranet. The hyperlinks can be created on a form in different ways. ö Create a field to store hyperlinks that will change for each record Open an existing table in Design view or create a new table. Type a field name for the field used to store the hyperlinks. In the Data Type column for that field, select Hyperlink. Save and close the design of the table. The table in design view is shown in Figure 60. Figure 60 Training Division, NIC, New Delhi 71

72 Open the table in Datasheet View to enter data. In E_mail field, Click Insert>> Hyperlink. In the insert hyperlink dialog box, select the appropriate tab for Link to and fill all the details. Figure 61 shows the details of Link to: Address Figure 61 Note : The hyperlink can be followed from the datasheet view of the form. 72 Training Division, NIC, New Delhi

73 ö Create a label that you can click to follow a hyperlink Open a form in Design view. Click Insert >>Hyperlink on the toolbar. In the Insert Hyperlink dialog box, specify a UNC path or a URL in the Link To File Or URL box, or click the Browse button to navigate to a file on your hard drive, or on a local area network. The hyperlink apprears on the form which can be placed anywhere on it ö Add a picture that you can click to follow a hyperlink Open a form in Design view. Click the Image Control tool in the toolbox, and then click on the form where you want to create the picture. From the Insert picture dialog box browse and select the graphic file you want to insert. After inserting the image, select the properties of the picutre by right-clicking on it. In the Hyperlink Address property, specify a path to a file on your hard drive, a UNC path, or a URL. ö Create a command button that you can click to follow a hyperlink Open a form in Design view. Click the Control Wizards tool in the toolbox to turn off the Control Wizard. Click the Button tool in the toolbox, and then click on the form where you want to create the button. Select the properties of the button. In the Hyperlink Address property, specify a path to a file on your hard drive, a UNC path, or a URL. Training Division, NIC, New Delhi 73

74 ö Charts and ActiveX Controls Add a new chart to a form Open the form in Design view. Click on Insert >>Chart. On the form, click where you want to place the chart. Follow the directions in the Chart Wizard, which creates the chart based on available tables or queries and the fields you select. Add an ActiveX control (OLE custom control) to a form Open a form in Design view. Click the More Controls tool in the toolbox. Click the control you want in the list. On the form, click where you want to place the control. Right-click the control, and then click Properties to open the ActiveX control property sheet. Set the necessary properties. ö Creating Sections The effectiveness of a form can be increased by adding one or more sections. Most forms have just a detail section, but a form can also include form header, page header, page footer, and form footer sections. To insert Form Header/Footer And Page Header/Footer Click View>> Form Header/Footer or Click View>> Page Header/Footer Give the appropriate title to the form in the Form Header section as shown in Figure Training Division, NIC, New Delhi

75 Figure 62 Training Division, NIC, New Delhi 75

76 q Reports A report is an effective way to present data in a required printed format because of control over the size and appearance of objects on a report. Most of the information in a report comes from an underlying table, query, or SQL statement, which is the source of the report s data. Other information in the report is stored in the report s design. E Creating a Report using Wizard Select Reports tab from the database window. Select New. The New Report dialog box appears as shown in Figure 63. Figure Training Division, NIC, New Delhi

77 Access gives various options for report creation. Report Wizard automatically creates a report based on the selected fields of the table/query selected. Click on Report Wizard. Select the table Employee on which the report is to be generated. The report picks up the name of the table to be taken as the title of the report. Click OK. Select the fields NAME, Date_of_birth, DESIGNATION, Salary from the list of available fields as shown in Figure 64. Figure 64 Select the fields by pressing. Click on Next. Next screen will appears as shown in Figure 65. Training Division, NIC, New Delhi 77

78 Figure 65 Based on a field, grouping level 9 can be added to a report. To skip grouping option, click Next. The next screen will appear as shown in Figure 66. Figure 66 9 Reports based on grouping levels and sort order will be explained later in the section. 78 Training Division, NIC, New Delhi

79 If sort order of records is not required, click on Next and you get the screen to decide the layout of the report as shown in Figure 67. Figure 67 Select the Report layout as Tabular and orientation as Portrait or Landscape. Click on Next, and you will get the screen as shown in Figure 68. Figure 68 Training Division, NIC, New Delhi 79

80 Select the Style for your report and click Next. Give title for your report as Employee and select option Preview the report and then select Finish as shown in Figure 69. Figure 69 Clicking on Finish, shows the Preview of the Report as shown in Figure 70 and the report file will be saved with same name as the title of report which can be changed. Figure 70 Report created using wizard option can be modified as and when required by going in design view of that report. 80 Training Division, NIC, New Delhi

81 E Creating a Report in Design View In the Database window, select Reports object. Click on New. In the New Report dialog box, click Design View. Select the name of the table or query and Click OK. For example, select table employee, that contains the data you want to base your report on. (If you want an unbound report, don t select anything from this list.) Click on View>>Field list (if the field list is not visible) and drag the required fields of the table in the detail section of report design view. Label for the fields should be written in page header and title for the report should be written in the report header. Page Header/Footer and Report Header/Footer options are selected by clicking View>>Page Header/Footer and View>>Report Header/Footer as shown in Figure 71. Figure 71 Click View>> Print Preview to get preview of the report as shown in Figure 72. Training Division, NIC, New Delhi 81

82 Figure 72 E Creating a Report for Mailing Labels This type of report is used to create labels from the database which can be used for the mailing purpose. In the Reports tab of Database window, click New. In the New Report dialog box, click Label Wizard. Select the table or query that contains the data for the labels, and then click OK. Follow the instructions in the wizard dialog boxes. The output of this report will be as shown in Figure Training Division, NIC, New Delhi

83 Figure 73 E Creating Calculated fields in the Report The calculated fields can be displayed on a report to show the results based on some calculations on a field. To include a calculated field, create a text box in the Detail section of the report in the design view. Write the expression for calculation in the Text box. Results would be displayed in Print Preview For example, if we have to calculate DA from the Basic of the employee, the expression in the text boxes for DA will be =[basic]*0.42 E Sorting and Grouping Records ö Sort records in a report Records in a report can be arranged in certain order depending on the sorting and grouping order defined. A report can be sorted on upto a maximum of 10 fields or expressions. Training Division, NIC, New Delhi 83

84 To create report in the sorted form, do the following steps: Open the report in Design view. Click on View>>Sorting And Grouping to display the Sorting And Grouping box as shown in Figure 74. In the first row of the Field/Expression column, select a field name, or type an expression as shown in Figure 74. Figure 74 The field or expression in the first row is the first sorting level (the largest set). The second row is the second sorting level, and so on upto 10 sorting levels can be defined. For each sorting level, sort order can be defined as Ascending or Descending. Click the field or expression whose group properties you want to set. Set the group properties in the following list. For each field defined in the sorting order, group properties can be defined. Either Group Header or Group Footer should be set to Yes in order to create a group level. GroupHeader. Adds or removes a group header for the field or expression. GroupFooter. Adds or removes a group footer for the field or expression. 84 Training Division, NIC, New Delhi

85 GroupOn. Specifies the value or range of values that starts a new group. The options you see depend on the data type of the field on which you re grouping. If you group on an expression, you see all the options for all data types. GroupInterval. Specifies any interval that is valid for the values in the field or expression you re grouping on. Keep Together. Keeps groups together on one page. Set the group properties as shown in Figure 75. Figure 75 The design view of the form will be appear as shown in Figure 76. Figure 76 Training Division, NIC, New Delhi 85

86 Note: When designing a report, the field on which grouping is to be done should be kept in Group Header section not in Detail section as Designation field is kept in Designation header section. The output will be appear as shown in Figure 77. Figure 77 E Calculating a Running Sum Running Sum property is used to calculate record-by-record or group-by-group totals in a report. The RunningSum property applies only to a text box and in the Design View of the report. Note : To open text box property sheet, first select the text box and click the right mouse button, select Properties from the option. 86 Training Division, NIC, New Delhi

87 ö To calculate running sum in a report Open report in Design View. Create Text Box in the Report Footer. Type Expression in the Text Box created at the Report Footer. For example, to calculate total salary given, type an expression : = Sum ( [Salary]) in Report Footer as shown in Figure 78. Figure 78 Note: Expression for the running sum can be given for more than one field in report footer. The output of this report will appear as shown in Figure 79. Training Division, NIC, New Delhi 87

88 Figure 79 Note: If calculation is to be made on Groups, the expression must be written in the Group footer. ö To include Serial No. in Report Open report in Design View. Create text box in Detail Section of report to calculate a record-by-record total. From the property sheet, click on either Data or All tab. Set ControlSource Property =1 and set the RunningSum property to Over Group. The Design View of the report appears as shown in Figure Training Division, NIC, New Delhi

89 Figure 80 The output for this design view appears as shown in Figure 81. Save this report as employee_detail. Figure 81 Note: To give S.NO. groupwise, place the text box in a group header and in the Text box property sheet, set RunningSum as OverGroup and ControlSource Property = 1. Training Division, NIC, New Delhi 89

90 E ö Different Types of Reports Multiple Column Report A multiple-column report can be used to print the report in more than one column. In this case Report Header/Footer and Page Header/Footer span the full width of the report, while Group Header/Footer and Detail Section span the width of one column. For example, if you want to print the data in two three-inch columns, place the controls within the width of one column; in other words, place the controls in the first three inches of these sections in Design view. Create a report and open it in Design View. On the File menu, click Page Setup. In the Page Setup dialog box, click the Columns tab. Under Grid Settings, in the Number Of Columns box, type the number of columns you want on each page. In the Row Spacing box, type the amount of vertical space you want between each record in the detail section. Note : If you left space between the last control in the detail section and the bottom edge of the detail section, you can leave Row Spacing set to 0. In the Column Spacing box, type the amount of space you want between the columns. Under Column Size, type the width you want for a column in the Width box; for example, 3. You can set the height of the detail section by typing a number in the Height box or by adjusting the height of the section in Design view. Under Column Layout, click suitable option as shown in Figure 82. Click the Page tab of the Page Set-up dialog box Under Orientation, click Portrait or Landscape. Click OK. 90 Training Division, NIC, New Delhi

91 Figure 82 Print preview of the Report is shown in Figure 83. Figure 83 Training Division, NIC, New Delhi 91

92 ö Crosstab Report Cross-tab Report is based on a Cross-tab query meant for analysing the data in a cross-tab format. Create a Crosstab query. In query Design View, display the query s property sheet by double-clicking anywhere outside the design grid and outside the field lists. In the ColumnHeadings property box, type the column headings you want to appear in the report, separating each one with a semicolon. If a column heading contains spaces, enclose it in double ( ) quotation marks. For instance, in a query showing sales by quarter, you would type: CL Taken ; El Taken ; Medical Taken Create a blank report that is bound to the crosstab query. Add the controls for the fields you want to appear in the report. Place labels for the row headings and column headings in the page header. Place text boxes for the row headings and column values in the detail section. The report thus obtained is shown in Figure 84. Figure Training Division, NIC, New Delhi

93 q Switchboard and Custom Menus After creating the forms, reports etc. in the database, one needs to create a GUI menu (Graphics User Interface menu). It will helps in navigating among the various objects like forms, reports, macros, modules in the database. Various objects can be opened by clicking the various buttons on the Switchboard. E Creating a Single Page Switchboard Open the database containing forms, reports or other objects already created. Click Tools >> Database Utilities >> Switchboard Manager. If switchboard is created for the first time then Microsoft Access asks if you d like to create a switchboard, Click Yes. The following dialog box will appear as shown in Figure 85. Figure 85 Following options are available in Switchboard Manager: Close To close switchboard Manager. New To add new switchboard Page to Switchboard manager. Edit To add items to switchboard page. Delete - To delete switchboard Page. Make Default When switchboard manager has more than one page, make the main switchboard page default that will open first when switchboard is run. Training Division, NIC, New Delhi 93

94 Click Edit button of Switchboard page (shown in Figure 85) to create all the switchboard items of that page. The dialog box appeared as shown in Figure 86. Figure 86 Click New button to add switchboard items to this page. The dialog box appears as shown in Figure 87. Figure 87 In the Edit Switchboard Item dialog box, in the Text: field, type the text that is to be displayed for the Switchboard Item on the Switchboard page. Select the Command: to be executed. Depending on the selection of command, the next field of the dialog box changes. Enter the values as shown in Figure Training Division, NIC, New Delhi

95 Figure 88 Click OK. More items can be added to this Switchboard by clicking on New button in the Edit Switchboard Page dialog box and entering the information as done for the previous item. Table 1 shows the various items that can be added to this page. SN SWITCHBOARD SWITCHBOARD COMMANDS OBJECTS TO PAGE PAGE ITEMS BE EXECUTED 1 Main Switchboard 1.1 Enter Employee s Open form in Employee Details add mode (Form name) 1.2 Enter Leave Details Open form in Leave add mode (Form name) 1.3 Employee report Open report Employee (Report name) 1.4 Leave detail report Open Report Leave_detail of an employee (report name) 1.5 Exit Exit Application Table 1 : Switchboard items and their commands in Single page Switchboard Click Close, after adding all the switchboard items to the Edit Switchboard Page. Click Close Button of the Switchboard Manager Dialog box. You come back to database window. Training Division, NIC, New Delhi 95

96 Once the Switchboard is made, one form named Switchboard and a table named Switchboard items will appear in the database window in their respective objects. The Switchboard page for the above items will be appeared as shown in Figure 89. Switchboard Page Switchboard Page Items Figure 89 Running the Switchboard Click on Forms object in the database window. Select Switchboard form. Click on Open. Default Main Switchboard page will opened as shown in Figure Training Division, NIC, New Delhi

97 E Creating a Multiple Page Switchboard Note: If more than one switchboard pages is required, then first create all the pages in the Switchboard Manager dialog box. Click Tools >> Database Utilities >> Switchboard Manager. If switchboard is created for the first time then Microsoft Access asks if you d like to create a switchboard. Click Yes. The Switchboard Manager dialog box appears as shown in Figure 85. Click New in the Switchboard Manager Dialog box to add new page, the dialog box appeared as shown in Figure 90. Figure 90 Type the Name of the New Switchboard Page. Click OK. A new page is added to the Switchboard manager. Similarly, add all the Switchboard Pages to Switchboard Manager by clicking New button. The Switchboard Manager dialog box with all pages included will appear as shown in Figure 91. Training Division, NIC, New Delhi 97

98 Figure 91 ö To add items to the switchboard page Select the Switchboard page in which Items has to be added. For example, select Main Switchboard page. Click Edit in the Switchboard Manager dialog box to edit all the items in that page. The Edit Switchboard dialog box will appear as shown in Figure 92. Figure Training Division, NIC, New Delhi

99 Click New. In the Edit Switchboard Item dialog box, do the following settings. Text/List box name Text Command Switchboard Value Maintain Employee s Data Go to Switchboard Update Employee Click OK after doing all the settings as shown in Figure 93. Figure 93 Add rest of the items to the same switchboard by following the above three steps. The page containing all the items will be appears as shown in Figure 94. Figure 94 Training Division, NIC, New Delhi 99

100 Click Close. Similarly add all the items to the rest of the pages of the Switchboard. Note: Block Diagram and Table 2 are provided in the following pages to add all switchboard items and their commands for all switchboard pages. ö ö Edit or Delete items Open the switchboard page in Edit mode. Click the item in the Items On This Switchboard box. Click Edit or Delete depending on the requirement. To rearrange items Open the switchboard page in Edit mode. Click the item in the Items On This Switchboard box. Click Move Up or Move Down to change the order of the item. 100 Training Division, NIC, New Delhi

101 Block Diagram for Multiple Page SwitchBoard Main SwitchBoard Page Page Items 1) Maintain Employees Data ( To open New Switchboard Page, Update Employee) 2) Enter Leave Details ( To open Leave Form) 3) Year End Processing ( To Run Macro) 4) Reports ( To open new switchboard page, Reports) 5) Exit ( To exit from an application) Update Employee Page 4) Add New Employee ( To open Employee form in Add mode) 5) Modify Employee Data ( To open Employee form in Edit mode) 6) Delete Employee Data ( To run Macro, Macro_Delele_emp_Records) Reports Page 4) Employee Report (To open Report Employee ) 5) Creating Employee Label ( To open report Employee Label ) 6) Leave Details of Individual employee ( To open report Leave ) Training Division, NIC, New Delhi 101

102 SN SWITCHBOARD SWITCHBOARD COMMANDS OBEJCT TO PAGE PAGE ITEMS BE EXECUTED 1 Main Maintain Goto Switchboard Update Switchboard Employee s Data Employee s Detail Enter Leave Open form in Leave Details Edit Mode Year End Run Macro Processing Reports Goto Switchboard Reports Exit Exit Application - 2 Update Add New Open form in Employee Employee s Employee Add Mode Detail Modify Employee Open form in employee Data edit mode Delete Employee Run Macro Macro_Delele_ Records emp_records Exit Go to switchboard Main Switchboard 3 Report Employee Report Open Report employee Creating Employee Open Report Labels employee Labels Exit Go to Main Switchboard Switchboard Table 2 : Switchboard items and their commands in Multiple page Switchboard 102 Training Division, NIC, New Delhi

103 Running Multiple Page Switchboard Click on Forms object. Select Switchboard form. Click on Open. Default Main Switchboard page will open first as shown in Figure 95. Figure 95 Click on the appropriate button to execute the command. Training Division, NIC, New Delhi 103

104 E Adding Picture to the Switchboard Open the Switchboard form in Design mode. It will be appeared as shown in Figure 96. Press Right mouse button in this portion Figure 96 Press right mouse button and select properties option, following dialog box will appear as shown in Figure 97. Figure 97 Click on the Picture property, specify the picture file name with complete path. For example, c:\program Files\Microsoft Office\Office\Bitmaps\Dbwiz\ledger.gif. 104 Training Division, NIC, New Delhi

105 The picture will be added to the switchboard as shown Figure 98. Figure 98 E Deleting a Switchboard To delete Switchboard from the access database Delete Switchboard Items table from tables object. Delete Switchboard form from the form objects. E Making Switchboard Page as a Startup Object The Switchboard can be kept in such a way that when the database is opened, Switchboard open first and from their the items can be selected. Click Tools>>Startup, dialog box as shown in Figure 99 will appear. Training Division, NIC, New Delhi 105

106 Figure 99 Give application title name and in Display Form/Page option give default Switchboard page name as shown in Figure 100. Figure 100 Click OK. 106 Training Division, NIC, New Delhi

107 E Creating Custom Menus Open database to which Custom Menu is to be added. Click View >> Toolbars>> Customize. Customize dialog box will appear as shown in Figure 101. Figure 101 Click Toolbars tab (If it is not already active) and choose New. Type Main menu in the text box in New Toolbar dialog box as shown in Figure 102. Click OK. Figure 102 Training Division, NIC, New Delhi 107

108 Item Main menu will be added to the Toolbars list. Select Main menu option from Toolbars, if not already selected. Click on Properties button. Select Menu Bar in the Type list box as shown in Figure 103. Figure 103 Selecting Menu Bar in the Type: box creates Main menu with no items and it appears on screen as shown in Figure 104. Figure 104 Close the Toolbar Properties dialog box. 108 Training Division, NIC, New Delhi

109 ö To add items to this menu bar Click Commands tab in Customize dialog box. Select New Menu as shown in Figure 105. Figure 105 Drag New Menu from the command list to the Main menu menu bar. Right click on New Menu in the Main menu and type Update Employee in the Name text box as shown in Figure 106. Figure 106 Similarily add all items to custom menu as shown in Figure 107. Training Division, NIC, New Delhi 109

110 Figure 107 In Main menu, click Update Employee menu option. An empty box will appear. The forms would now be added to this. ö To add commands to it In the Customize dialog box, select Command tab, if not already selected. Click All Forms from Categories. Drag the command employee to the empty box and rename it as Add Employee. Similarly, drag the command Leave and rename it as Leave Details. Click All Macros from Categories. Drag the macro designed for deleting records and rename it as Delete Employee. The Main menu designed is shown in Figure 108. Figure 108 Similarily other items can be added to the various menu options. For example, add items to Year End Processing and Reports menu options. 110 Training Division, NIC, New Delhi

111 E Making Custom Menu as a Startup Object Click Tools>>Startup. In the Startup dialog box, select Main menu in the Menu Bar text box as shown in Figure 109. Figure 109 Click OK. When database is opened, Main menu will appear as shown in Figure 110. Figure 110 Training Division, NIC, New Delhi 111

112 E Restoring Default Menu For restoring the default database menu bar, Point your mouse cursor to the database title bar and Click right mouse button. Popup menu will appear as shown in Figure 111. Figure 111 Database title bar Click on Startup option and change the setting of the Menu Bar to Default. Close this application and when you open database again, Default menu bar will appear again. 112 Training Division, NIC, New Delhi

113 q Importing and Exporting Data Importing and exporting data helps in exchanging data from a number of different databases, spreadsheet, and text file formats with the help of built-in drivers or ODBC drivers 10. Importing, Linking and Exporting are the different ways used for the exchange of data in MS Access. E Exporting Exporting is a way to output data and database objects to another database, spreadsheet, or file format so that another database, application, or program can use the data or database objects. The various types to which they can be exported are: 1. Microsoft Access 2. Dbase 3. Excel 4. Foxpro 5. HTML documents 6. Paradox 7. Text Files 8. Rich Text Format 9. Microsoft IIS 10. ODBC databases 11. Microsoft Word Merge 10 For details refer to Annexure III Training Division, NIC, New Delhi 113

114 Steps for Exporting data Open the Access Database Employee created earlier. Select the Table/Query which is to be exported, in this case select Leave. Click File>>Export. Following dialog box will appear as shown in Figure 112. Figure 112 Specify the file name as Leave and the type as Microsoft Excel , to which it is to be exported, in the respective text boxes. Click Save. Thus the data of the Leave table gets exported to an Excell worksheet named Leave. 114 Training Division, NIC, New Delhi

115 Now this file can be opened in Ms-Excel for further editing. Any changes in Excel file will not be reflected in data stored in MS-Access table/query. Note : The data from Access can be exported to other file formats, specified earlier, in the same manner, selecting the Save As type for the desired format. E Importing Importing data creates a copy of its information in a new table in your Access database or Access project. The source table or file is not altered in this process. When importing data, you can t append data to existing tables (except when importing spreadsheet or text files). However, once you have imported a table, in an Access database you can perform an append query 11 or in an Access project you can use a stored procedure 12 to add the table s data to another table. You can also import database objects other than tables, such as forms or reports, from another Access database or Access project. The various types from which data can be imported are: Microsoft Access Dbase Excel Foxpro HTML documents Paradox Text Files Rich Text Format ODBC databases Exchange 11 An action query that adds the records in a query s result set to the end of an existing table. 12 A precompiled collection of SQL statements and optional control-of-flow statements stored under a name and processed as a unit. Stored procedures are stored in an SQL database such as Microsoft SQL Server, usually on a server; can be run with one call from an application; and allow user-declared variables, conditional execution, and other powerful programming features. Training Division, NIC, New Delhi 115

116 Steps for Importing data Open the Access Database. Click File>>Get External Data>>Import. Following dialog box will appear as shown in Figure 113. Figure 113 Select the type of file and the name of file from which data is to be imported. Click Import. Depending on the type of the file from which data is to be imported, the further options have to be chosen. For example, if data is imported from an Access database, following window will appear as shown in Figure Training Division, NIC, New Delhi

117 Figure 114 The various objects of the database are listed and the data desired from any of these objects can be selected. Click OK. If it is an Excel file then a 6-step wizard will start which will ask for the following options: Worksheet or Range to be imported. Specify whether first row of data contains column headings or not. Whether the data is to be imported in a new table or existing ones. Specify the field option for all fields. Information about primary key. If it is a new table, then table name. Click Finish. Similar steps with minor differences can be followed for other types of files. For example, Microsoft Access, Dbase, Excel, Foxpro, HTML documents, Paradox, Text Files, Rich Text Format, ODBC databases, Exchange. Training Division, NIC, New Delhi 117

118 E Linking In an Access database, linking data enables you to read and in most cases, update data in the external data source without importing. The external data source s format is not altered so that you can continue to use the file with the program that originally created it, but you can add, delete, or edit its data by using Microsoft Access as well. You can link a table only in an Access database, not in an Access project. Microsoft Access uses different icons to represent linked tables, for example if Excel sheet is linked then icon will be, under the Tables object tab and other tables that are stored in the current database. If you delete the icon for a linked table, you delete the link to the table, not the external table itself. Linking is done by Select File >> Get External Data >> Link Tables... Link dialogue box appears where file name and File type can be specified. Click Link. Note: The design of the table, thus linked, cannot be altered since it is linked with the source. 118 Training Division, NIC, New Delhi

119 E Assignments I. Importing data from Excel Worksheet to MS Access 1. Create a simple Excel Worksheet with first row as field names and five rows filled with some data ( E-code, Name, designation, qualification, Controlling Officer) 2. Save the Excel Worksheet. 3. Open already existing Database ( say employee) through MS Access. 4. Right click on database and select Import option. 5. Choose appropriate folder and type of file as Excel. 6. Select already created Excel file in step Through Wizard make appropriate selections and create a new table containing data from Excel Worksheet. II. Importing text file to MS Access 1. Create a file using Notepad containing data items separated by,. 2. Open Employee database in MS Access. 3. Right click on database and select Import option. 4. Choose appropriate folder, and type of file as Text. 5. Select already created text file. 6. Through Wizard select appropriate options and create a new table with data picked up from Text file. 7. View the newly created table. Training Division, NIC, New Delhi 119

120 III. Exporting Data from a table/query to Excel Worksheet 1. Open database employee. 2. Choose table (say employee table). 3. Click on File>>Export. 4. Select file type as MS Excel and click Save. 5. View the new file in MS Excel. 6. Repeat the above steps with a Query already created in database Employee. IV Exporting data from a table / query to HTML page 1. Open database Employee. 2. Choose table Employee. 3. Click on File>>Export. 4. Select file type as HTML and click Save. 5. View the new file through Internet Explorer or MS Word. 6. Repeat the above steps with a Query already created in database Employee. V Publishing MS Word / MS Excel Report to MS Word/Excel file 1. Open database Employee. 2. Choose an already created report. 120 Training Division, NIC, New Delhi

121 3. Click on office links on the toolbar as shown in Figure 115. Office links Figure Click on option Publish it with MS Word / Analyse it with MS Excel View the newly created Word / Excel file. VI Mail Merge in MS Word with data from MS Access table /Query 1. Open Database in MS Access. 2. Select the table / query from which you want to merge fields in a MS Word document. 3. From the office links dropdown list select the option Open MS Word Document. 4. Choose the option Create a new document / link your data to an existing word document. 5. In the MS Word window, type the matter, and insert fields from the special Mail Merge window, which appears as shown in Figure Now you may generate letter. Training Division, NIC, New Delhi 121

122 Figure Training Division, NIC, New Delhi

123 Annexures

124

125 q Annexure I Various Data Types are given in the following table Data Type Text Memo Number Date/Time Currency AutoNumber Yes/No OLE Object Hyperlink Description holds text up to 255 characters, including letters, numbers and special characters. holds text up to characters, is of variable length: you do not specify a maximum size for it. holds numeric data. holds date and time. You can enter Date/Time on the format you select for the field. holds number used as amounts of money. holds sequential numbers that Access automatically enters. holds two values, defined as Yes/No, True/False or On/Off, depending upon the format you give to it in the field properties panel. holds data from other Window application that support object linking and embedding. This field can be used to attach pictures, Sound Files or any other type of data available from Windows applications that supports OLE. holds the address of an object, document or web page, which you can display simply by clicking the field. Lookup Wizard lets you create a lookup field where user chooses values from the list of values entered or taken from the table. Training Division, NIC, New Delhi A 1.1

126

127 q E Annexure II Field Properties Field properties can be changed by using the options on the General and Lookup tabs in the field properties pane in the table design window. Different data types offer different properties. Note : The field properties area of the table design window shows only one field property at a time. Make sure that the arrow symbol should appear before the selected field. Field properties area is shown in Figure 117. Figure 117 Training Division, NIC, New Delhi A 2.1

128 General Field Properties ö Field Size FieldSize property is used to set the maximum size for data stored in a field set to the Text, Number, or AutoNumber data type. Settings: Data Type Default Setting Settings Allowed Size Text 50 Number from 0 to 255 AutoNumber Long Integer Long Integer or Replication Id Number Long Integer 4 Byte Byte 1 Byte Decimal 12 Byte Integer 2 Byte Single 4 Byte Double 8 Byte Replication 16 Byte Note : Use the smallest possible FieldSize property setting because smaller data sizes can be processed faster and require less memory. Caution : If you convert a large FieldSize setting to a smaller fieldsize that already contains data, you might lose data. ö Format Format property is to customize the way in which Numbers, Date, Time, and Text are displayed and printed. For example, in a Price text box, its Format property is set to Currency and its Decimal Places property to 2 or Auto. If you enter in the control, the number would be displayed as $4, A 2.2 Training Division, NIC, New Delhi

129 The Format property provides different settings for different data types. Date/Time Data Type Number and Currency Data Types Text and Memo Data Types Yes/No Data Type Note : The Format property affects only how data is displayed. It doesn t affect how data is stored. Following symbols can be used in custom formats for any data type: Symbol Meaning (space) Display spaces as literal characters. ABC Display anything inside quotation marks as literal characters.! Force left alignment instead of right alignment. * Fill available space with the next character. \ Display the next character as a literal character. You can also display literal characters by placing quotation marks around them. [color] Display the formatted data in the color specified between the brackets. Available colors: Black, Blue, Green, Cyan, Red, Magenta, Yellow, White. ö Input Mask InputMask property is used to make data entry easier and to control the values, users can enter in a text box control. For example, an input mask for a Phone Number field that shows, exactly how to enter a new number: ( ) -. Training Division, NIC, New Delhi A 2.3

130 An input mask can be defined by using the following characters: Character Description 0 Digit (0 to 9, entry required, plus [+] and minus [ ] signs not allowed). 9 Digit or space (entry not required, plus and minus signs not allowed). # Digit or space (entry not required; spaces are displayed as blanks while in Edit mode, but blanks are removed when data is saved; plus and minus signs allowed). L Letter (A to Z, entry required).? Letter (A to Z, entry optional). A Letter or digit (entry required). a Letter or digit (entry optional). & Any character or a space (entry required). C Any character or a space (entry optional).., : ; - / Decimal placeholder and thousand, date, and time separators. (The actual character used depends on the settings in the Regional Settings Properties dialog box in Windows Control Panel). < Causes all characters to be converted to lowercase. > Causes all characters to be converted to uppercase.! Causes the input mask to display from right to left, rather than from left to right. Characters typed into the mask always fill it from left to right. You can include the exclamation point anywhere in the input mask. \ Causes the character that follows to be displayed as the literal character (for example, \A is displayed as just A). Note : Setting the InputMask property to the word Password creates a passwordentry control. Any character typed in the control is stored as the character but is displayed as an asterisk (*). A 2.4 Training Division, NIC, New Delhi

131 The following table shows some useful input masks and the type of values can be entered: Input mask Sample values (000) (206) (999) (206) or ( ) (000) AAA-AAAA (206) 555-TELE # or 2000 >L????L?000L0 GREENGR339M3 or MAY R 452B7 >L0L 0L0 T2F 8M or >L<?????????????? Maria or Brendan SSN SSN >LL DB ö Caption Caption property provides helpful information to the user through captions on objects in various views: Field captions specify the text for labels attached to controls created by dragging a field from the field list and serves as the column heading for the field in table or query Datasheet view. Form captions specify the text that appears in the title bar in Form view. Report captions specify the title of the report in Print Preview. For Example, Field Name Emp_code Ename Caption Employee Code Employee Name The result with these caption is shown in Figure 118. Training Division, NIC, New Delhi A 2.5

132 Caption appeared as column Heading in Datasheet view Figure 118 Note : Include two ampersands (&&) in the setting for a caption if you want to display an ampersand itself in the caption text. For example, to display Save & Exit, type Save && Exit in the Caption property box. è Default Value DefaultValue property is to specify a value that is automatically entered in a field when a new record is created. For example, in an Addresses table you can set the default value for the City field to New York. When users add a record to the table, they can either accept this value or enter the name of a different city. Note : The DefaultValue property doesn t apply to check box, option button, or toggle button controls when they are in an option group. It does apply to the option group itself. A 2.6 Training Division, NIC, New Delhi

133 The DefaultValue property applies to all table fields except those fields with the data type of AutoNumber or OLE Object. Default values that can be assigned to a field Default Value Value Data Type =Date() Today s date Date/Time =Now() Current date and Time Date/Time 0 Number zero Number or Currency Yes True Yes/No No No Yes/No CA Letter CA Text ö ValidationRule and ValidationText Properties The use of ValidationRule property is to specify requirements for data entered into a record, field, or control. When data is entered that violates the ValidationRule setting, ValidationText property can be used to specify the message to be displayed to the user. Note: The ValidationRule and ValidationText properties don t apply to check box, option button, or toggle button controls when they are in an option group. They apply only to the option group itself. In ValidationRule - Enter an expression Maximum length 2048 Character. In ValidationText Enter a Text Maximum length 255 Character. If ValidationRule property Set ValidationText property is Not Set, Standard error message will be displayed. ValidationText property is Set, text entered will be displayed as the error message. For example, A ValidationRule property can be set for the employee s Salary field to be >0. If Salary is Less than or equal to Zero, It display the ValidationText property message: Salary must be greater than zero. Training Division, NIC, New Delhi A 2.7

134 Examples for the ValidationRule and ValidationText properties: ValidationRule property ValidationText property <> 0 Entry must be a nonzero value. > 1000 Or Is Null Entry must be blank or greater than Like A???? Entry must be 5 characters and begin with the letter A. >= #1/1/96# And <#1/1/97# Entry must be a date in DLookup( CustomerID, Entry must be a unique CustomerID Customers, CustomerID = Forms! (domain aggregate functions are allowed Customers!CustomerID ) Is Null only for form-level validation). Note : If validation rule is set for a field, Microsoft Access doesn t normally allow a Null value to be stored in the field. If you want to allow a Null value, add Is Null to the validation rule, as in <> 8 Or Is Null and set Required property to NO. è Allow Zero Length property AllowZeroLength property is used to specify whether a zero-length string ( ) is a valid entry in a table field. Note : The AllowZeroLength property applies only to Text, Memo, and Hyperlink table fields. The AllowZeroLength property uses the following settings: Setting Yes No Description A zero-length string is a valid entry. (Default) A zero-length string is an invalid entry. A 2.8 Training Division, NIC, New Delhi

135 ö Required AllowZeroLength User s action Value stored No No Presses ENTER Null Presses SPACEBAR Null Enters a zero-length string (not allowed) No Yes Presses ENTER Null Presses SPACEBAR Null Enters a zero-length string Zero-length string Yes No Presses ENTER (not allowed) Presses SPACEBAR (not allowed) Enters a zero-length string (not allowed) Yes Yes Presses ENTER (not allowed) Presses SPACEBAR Zero-length string Enters a zero-length string Zero-length string ö Required Property Required property is used to specify whether a value is required in a field. If this property is set to Yes, then it is must to enter the value in that field. Note: The Required property doesn t apply to AutoNumber fields. Results from combined settings of the Required and AllowZeroLength properties are: Indexed Property Indexed property is used to set a single-field index. An index speeds up queries on the indexed fields as well as sorting and grouping operations. For example, search for specific employee names in a ename field of employee table, create an index for this field to speed up the search for a specific name. The Indexed property uses the following settings: Setting Description No (Default) No index. Yes (Duplicates OK) The index allows duplicates. Yes (No Duplicates) The index doesn t allow duplicates. Training Division, NIC, New Delhi A 2.9

136 Remarks Use the Indexed property to find and sort records by using a single field in a table. The field can hold either unique or non-unique values. For example, an index on an Emp_code field in an Employee table in which each emp_code is unique or create an index on a ename field in which some names may be duplicates. If the primary key for a table is a single field, Microsoft Access will automatically set the Indexed property for that field to Yes (No Duplicates). Note : Indexed property is not applicable to Memo, Hyperlink, or OLE Object data type fields. Index can be created to any no. of fields in table. The indexes are created when table is saved and are automatically updated when records are changed or added. Indexed property can be added or deleted any time in table Design view. Lookup Properties To open lookup property sheet Switch to the design view of table. Select field. Click the Lookup tab in field property area. If Designation field is created as lookup field, it will appear as shown in Figure 119. Figure 119 A 2.10 Training Division, NIC, New Delhi

137 In datasheet view lookup field will be appeared as shown in Figure 120. Figure 120 Different options in Lookup properties are: Option Description Display Control This control is used to display the fields in Datasheet View (i.e. set property to List Box or Combo Box for Lookup fields) Row Source Type This control is used to choose the source of data in the fields(table/ query, Value List or Field List). Row Source Lets you choose the source of the control s data. In the above figure the row source is value typed. Bound Column This control is used to specify which column in the row source contains the value to store in lookup fields. As shown in above figure, the list box contains two columns but it will store the second column value in designation field so bound column value is 2. Column Count This property specifies how many columns to display. Column Heads This property is used to choose whether to show column headings. By default no column headings appear. To show column headings change setting to Yes. Training Division, NIC, New Delhi A 2.11

138 Column Widths List Rows List Width Limit to List It is used to specify the width of each column shown in drop down list. It specifies how many rows to display in the drop down list at once (by default is 8). It specifies the width of entire combo box. If set to Yes, only values shown in drop down list are allowed during data entry. If set to No, entries allowed that are not in drop-down list. A 2.12 Training Division, NIC, New Delhi

139 q E Annexure III Built-in drivers and ODBC drivers ö Built-in drivers are available when you use the l Export command on the File menu, l The Import and Link Tables commands on the Get External Data submenu on the File menu. l Save As Type box in the Export Object Object Name To dialog box, or l In the Files Of Type box in the Import or Link dialog boxes. All built-in drivers are installed automatically when you install Access. ö ODBC drivers are used to connect to l l Microsoft SQL Server databases, Microsoft FoxPro databases, Data from other programs that provide 32-bit drivers in compliance with ODBC Level 1 to access their data files. Microsoft Access automatically installs the Microsoft SQL Server ODBC driver (Sqlsrv32.dll), the FoxPro ODBC driver (vfpodbc.dll), the Oracle ODBC driver (msorcl32.dll), and some ODBC support files (Help files and the Control Panel ODBC (32bit) icon). The ODBC Databases option is available in the Save As Type box in the Export Object Object Name To dialog box. Files Of Type box on the Import or Link dialog boxes. ODBC (32bit) icon is available in Control Panel. ö How to create ODBC data source On the Windows desktop click Start>>Settings>>Control Panel. Double click on the ODBC icon in the control panel. ODBC datasource administrator wizard as shown in Figure 121 will start: Training Division, NIC, New Delhi A 3.1

140 Figure 121 From the screen appeared in Figure 121, select the driver name. Click Add. Figure 122 Specify the Data Source Name and select the database name by clicking on Select button, as shown in Figure 122. Click OK. Data Source Name will be listed in the ODBC database Administrator which can be used later on. A 3.2 Training Division, NIC, New Delhi

141 Notes

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145 Getting Started with MS-Access Government of India Ministry of Communications & Information Technology Department of Information Technology National Informatics Centre Training Division New Delhi

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147 Getting Started with MS-Access Government of India Ministry of Communications & Information Technology Department of Information Technology National Informatics Centre Training Division New Delhi

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149 Contents PART - I q An Overview of Database Management System 1 Components of an Information System Conventional Approach for Data Management Database Approach Types of Data Model Types of Database Architecture Database Management System Getting Started with Database Design Getting Started with MS-Access q Case Study 16 q Starting MS Access 20 Ways of Creating a Table Creating New Table Saving the Table Adding Records to a Table Deleting Records Editing Data in Tables Sorting Data Modifying Table Design Primary Key Creating Second Table

150 q Relationships 31 How it works? Creating New Relationships Editing the Existing Relationship q Query 39 Simple Query Performing Calculation in the Query Using Criteria or Advanced Filters to retrieve certain Records Parameter Queries Action Queries More about Queries Accessing Query through Form q Forms 59 Creating a Form using Wizard Creating a Form in Design View Different Controls Further Enhancements in Form Design q Reports 76 Creating a Report using Wizard Creating a Report in Design View Creating a Report for Mailing Labels Creating Calculated fields in the Report Sorting and Grouping Records

151 Calculating a Running Sum Different Types of Reports q Switchboard and Custom Menus 93 Creating a Single Page Switchboard Creating a Multiple Page Switchboard Adding Picture to the Switchboard Deleting a Switchboard Making Switchboard Page as a Startup Object Creating Custom Menus Making Custom Menu as a Startup Object Restoring Default Menu q Importing and Exporting Data Exporting Importing Linking Assignments q Annexures

152 A Word with the Participant The conventions followed in this workbook are given below: (i) The steps/commands, the user has to perform, are preceded by the symbol. For example : Switch on the Computer. (ii) (iii) The matter to be typed by the user appears in this typeface. For example : Type My First File. The options/sub options to be selected or the messages given by the system, appear in the Bold font; For example : Select the File >> New option. This means that first click on the File menu and then click on the sub option New from its drop down menu. (iv) (v) (vi) The button to be selected appears in Bold font and the selection is through clicking the mouse. For example : Click the Cancel Button. The keys to be pressed on the keyboard are shown in Italic font. For example : Press the Enter key. Additional information, if any, is mentioned in the boxes, which can be skipped by the first timers, if desired. Kindly note that these work books are designed for self learning. It is therefore important that you follow the sequence of steps given in the work book. Happy Learning!!! (NIC Faculty) Training Division, NIC, New Delhi