Table of Contents SUMMARY...3 CONTEXT OF THE APPLICATION...4 FUNCTIONALITY...5 FUNCTIONAL DETAILS...6 SAMPLE USE CASE 1 IDENTIFY DIVERGENT FILE STRUCTURES... 10 SAMPLE USE CASE 2 LOCATE TABLES CREATED BY SQL STATEMENTS... 11 SAMPLE USE CASE 3 SEARCH FOR FIELD NAMES AND OBTAIN ADDITIONAL INFORMATION... 13 CONTACT AND FURTHER INFORMATION... 14 Page 2 / 14
Summary The Lerox DB/2 Database Dictionary for System AS/400, iseries i5, System i is a QlikView application that provides easy structural analysis of any DB/2 database on these systems. It can be used to locate data and create script snippets for the data modeling phase of QlikView application design. Target groups are database administrators and QlikView application developers that require data from DB/2 data sources for their analysis. The application consists of two parts: The first file is connected directly to a DB/2 database. It is used to load the repository, transform fields to show interconnections and save everything in a QlikView optimized file format. The second part provides an intuitive QlikView user interface for analysis. Installation only requires three steps: At first a user with sufficient reading rights to load all relevant data needs to be created on the DB/2 system. Then an ODBC connection needs to be established and added to the load script of the DB/2 Database Dictionary. Lerox has more than two decades of experience with DB/2 databases and started developing DB/2 analysis applications in QlikView in 2003. The DB/2 Database Dictionary has been useful in client installations for many years. Please contact Lerox Account Manager Markus Baumgartner at +43 676 740 7890 or markus.baumgartner@lerox.at for further details. Page 3 / 14
Context of the application Throughout the years, IBM solutions have been using the integrated database called DB/2 for the operating systems OS/400 and I5/OS later on. AS/400 used to be the name of the corresponding hardware for a long period of time and is still frequently used, even when referring to the newer iseries or System i. Summary of IBM product names over the past decades Page 4 / 14
Functionality As most QlikView developers know, sqltables is a very useful command for development. It is used to combine an array of fields from an ODBC data source in tables. Together with fields generated by the commands sqlcolumns and sqltypes these fields show structure and properties of a database. In context of AS/400 systems this information is usually not sufficient as DB/2 is not an SQL database per-se - structure and management are significantly different. Additional information regarding fields, their occurrence, access paths, etc. is required. At this point the Lerox DB/2 Database Dictionary can be used in to provide simple access to the additionally required information. The Database Dictionary itself consists of two QlikView applications. The data loader application determines and locates data in the DB/2 repository and saves the information to QlikView optimized QVD files (i5_get_db2_repository_into_qvd.qvw). The data loader also translates content of certain fields. The actual collection of data is determined by the ODBC connection, the overall number of tables and the libraries where data tables are saved. For large, complex systems this automated process can take up to an hour. A database user is required to connect the Database Dictionary application to the DB/2 database via ODBC. This user needs to be able to read the libraries QSYS, QSYS2 and QUSRSYS, users in the class *PGMR usually have the appropriate rights. As soon as QlikView optimized QVD files have been created by the first application of the Lerox Database Dictionary, the second application (i5_display_db-file-field-structure.qvw) can be used for in depth analysis as it allows direct access to the DB/2 database repository and to additional Meta information. In addition QlikView Developers can easily run various queries on tables and fields. They can also copy selected fields to their QlikView load scripts and correspondingly rename fields to self-explaining expressions (by default the existing field text is used). Page 5 / 14
Functional Details Folder (Library) of tables (Files) Name of a table (file) Record format (see below for details) Owner of the table (file) Screenshot 1: Main screen of the analysis application of the database dictionary right after start Page 6 / 14
Details on record format Record formats are specific to the DB/2 for ibusiness. Groups can be created in database files (tables) that contain multiple fields. This allows uniting multiple files (tables) in a logical view. In the conceptual view of the database design one example may be an order head, order details and maybe an additional order free text that are joined via a common key like company or order number. Standard QlikView cannot process such logical files as there are no equivalents for them in SQL. Screenshot 2: Selection of a library (folder) and a file (table) to access additional details Page 7 / 14
Screenshot 3 - Detail view on structure table: This example shows a file (table) with two key fields. Screenshot 4 - Detail view on Meta information File-Attr, PF, LF, TB, ID (Specific to DB/2 on AS/400): PF [Physical File (table)] and LF [Logical File]: File D=Data, S=Source (Specific to DB/2 on AS/400): D marks a file (table) that is managed by the DB/2 Database Management in all instances (usually files that contain client data). S marks a file (table) that is also managed by the DB/2 Database Management but contains program code for application development. Page 8 / 14
Screenshot 5 Detail view: Mapping table for field name conversion Screenshot 4: Tab for display and export of QlikView script snippets When working with QlikView self-explaining field names are very important. Field names in DB/2 systems are very technical; therefore the DB/2 Database Dictionary offers a mapping table and a script generator that translates DB/2 field names into selfexplaining names for use in the QlikView data model. Page 9 / 14
Sample Use Case 1 Identify divergent file structures A search for the file BUP returned an associative analysis showing that this file exists in multiple libraries and that there are multiple owners for the file. Even more interesting is the fact that the files (tables) have varying structures (field structure) across libraries. In a relational database something like this should not happen. Still, in many cases such a state cannot be entirely eliminated in practice because of a necessity for different development versions, while a DB/2 repository always manages and displays all files (tables) of a system. Page 10 / 14
Sample Use Case 2 Locate tables created by SQL statements DB/2 files (tables) that were created using SQL statements can easily be identified and selected using the file type box of the DB/2 database dictionary. Currently the following selections are possible: Index (SQL) Objects created via create index Logical File (DDS) Objects created via DDS and the system command CRTLF Physical File (DDS) Objects created via DDS and the System command CRTPF Remote File DDM Objects created via System Commands (CRTDDMF) Table (SQL) Objects created via SQL create table View (SQL) Objects created via SQL create view A counter next to the selection displays the total number of occurrences in a system. Data objects can be accessed directly via further selection in library and/or file. Page 11 / 14
In the following example, selection of file type View and table CHECK_CSTS returns that this file occurs in both the QSYS2 and SYSIBM libraries. Page 12 / 14
Sample Use Case 3 Search for field names and obtain additional information Another very common question regarding DB/2 databases is where a specific field name occurs. This can be easily answered with the DB/2 Database Dictionary. In this example the length of the field OP#BU needs to be altered in the database. To locate all occurrences in the database the field is selected in the DB/2 Database dictionary. The resulting associative analysis offers a lot of useful information like the total number of occurrences in files (tables) or in which libraries (folders) these tables are stored. Also data type of a table (D/S) and its owner can be easily identified. Page 13 / 14
Contact and further Information Lerox is a well-established IT solution provider with the largest dedicated QlikView team in Austria. The team is serving customers in Austria and Germany with data analysis and QlikView since 2004. From the very beginning analysis for AS/400 systems (and predecessors) are one of the key specialties of the team. Customers who are successfully using the DB/2 Database Dictionary include: Please contact Lerox Account Manager Markus Baumgartner at +43 676 740 7890 or markus.baumgartner@lerox.at for further details. Page 14 / 14