BAAN IV. Oracle Database Driver Technical Reference Manual

Transcription

1 BAAN IV Oracle Database Driver Techical Referece Maual

2 A publicatio of: Baa Developmet B.V. P.O.Box AC Bareveld The Netherlads Prited i the Netherlads Baa Developmet B.V All rights reserved. The iformatio i this documet is subject to chage without otice. No part of this documet may be reproduced, stored or trasmitted i ay form or by ay meas, electroic or mechaical, for ay purpose, without the express writte permissio of Baa Developmet B.V. Baa Developmet B.V. assumes o liability for ay damages icurred, directly or idirectly, from ay errors, omissios or discrepacies betwee the software ad the iformatio cotaied i this documet. Documet Iformatio Code: U7155A US Group: User Documetatio Editio: A Date: October, 1998

3 Table of cotets 1 BAAN IV database driver overview 1-1 The BAAN IV architecture 1-1 Display tier 1-2 Applicatio tier 1-3 Database tier 1-3 Data flow through the BAAN IV architecture 1-4 BAAN IV hardware cofiguratios 1-5 Level 1 ad Level 2 database drivers BAAN IV database orgaizatio 2-1 BAAN IV data dictioary 2-1 Table amig covetio 2-2 Colum amig covetio 2-3 Idex amig covetio 2-4 Data type mappig 2-5 Additioal costraits Database driver iteral processig 3-1 Data itegrity 3-1 Referetial itegrity 3-1 Distributed databases 3-2 Data bufferig 3-2 Database driver SQL processig 3-2 The Oracle call iterface (OCI) 3-2 SQL processig 3-3 To set driver behavior 3-4 Driver resources 3-5 Eviromet variables 3-6 Storage file 3-8 i

4 Table of cotets 4 Database security 4-1 Database security 4-1 Groups 4-2 Object security 4-3 Autheticatio 4-4 DBA module 4-5 Utility programs orax_admi6.1 ad orax_mait orax_admi orax_mait Database driver profilig ad statistics 5-1 Profilig 5-1 Level 1 profilig example 5-2 Level 2 profilig example 5-3 Gatherig statistics 5-4 Troubleshootig 5-6 To log database driver trace iformatio 5-6 To log errors Database driver cofiguratio ad tuig 6-1 Cursor maagemet 6-1 Level 1 mode 6-1 Level 2 mode 6-2 Array iterface 6-3 Idex optimizatio 6-4 Duplicate idexes 6-6 Hash colum amig covetio 6-6 Size of hash colums 6-6 Idex optimizatio 6-7 Fetch optimizatio 6-7 Row cachig 6-8 Query tuig 6-9 Cocateated expressios 6-9 Descedig jois 6-11 Specifyig query tuig 6-11 Optimistic ad pessimistic referece checks 6-11 Lockig behavior 6-12 Implicit ad explicit lockig 6-12 Delayed lockig 6-13 Statemet ad lock timeouts 6-13 High-level lock retries 6-14 ii

5 Table of cotets 7 Appedix A: Database driver resources ad eviromet variables 7-1 Summary of Oracle resources ad eviromet variables 7-1 Detailed descriptio of Oracle resources ad eviromet variables 7-4 Geeric driver resources 7-5 Oracle driver specific resources 7-13 Resources passed to the Oracle database server 7-19 Usig SQL*Net or Net Appedix B: Storage file format ad cofiguratio optios 8-1 Storage file format 8-1 Storage file field descriptios 8-2 iii

6 Table of cotets iv

7 About this documet This documet supplies techical referece iformatio about the BAAN IV database driver for Oracle. This documet applies to both Oracle7 ad Oracle8 ad for the BAAN IV Level 1 ad Level 2 database drivers. Whe o metio is made of the Oracle versio or the BAAN IV database driver level, the iformatio applies to all variatios. Ay differeces are explicitly stated. This documet is iteded for those who wat to cofigure or customize the BAAN IV database driver for Oracle. Both the database driver ad the Oracle database server ca ru o either a UNIX system or a Widows NT system. You should have a elemetary kowledge of UNIX or Widows NT ad Oracle as well as a uderstadig of database techology. This documet also describes the BAAN IV database driver that forms the iterface betwee the BAAN IV applicatio server layer ad the Oracle database server. The formal ame for this database driver is the BAAN IV database driver for Oracle. For simplicity, the database driver is referred to as the BAAN IV Oracle driver. The procedures for istallig Oracle ad BAAN IV are described i the Oracle Istallatio for BAAN IV o UNIX (U7028B US) or i the Oracle Istallatio for BAAN IV o Widows NT (U7051D US). This documet is divided ito the followig six chapters ad two appedices: Chapter 1 provides a overview of the BAAN IV database driver architecture ad a explaatio of how the database driver fits withi the total BAAN IV architecture. Chapter 2 describes the BAAN IV database orgaizatio ad details the amig covetios used for data withi the Oracle database. Chapter 3 describes some of the iteral features of the BAAN IV Oracle database driver. Chapter 4 describes the BAAN IV admiistratio tools for the BAAN IV Oracle database driver. Chapter 5 describes the facilities for profilig ad gatherig statistics about database driver performace. v

8 About this documet Chapter 6 details the cofiguratio ad tuig optios for the BAAN IV Oracle database driver. Appedix A supplies iformatio about the database driver resources ad eviromet variables that ca be used o both the cliet ad the server. Appedix B cotais iformatio about the file format of the storage file ad the driver cofiguratio optios specific to the BAAN IV Oracle database driver. vi

9 1 BAAN IV database driver overview The database driver plays a importat role i Baa s commitmet to a ope systems cliet/server architecture. Because the BAAN IV architecture icludes both the BAAN IV software ad a third-party relatioal database maagemet system (RDBMS), the driver is eeded to provide a seamless iterface betwee the BAAN IV software ad the differet RDBMS products. The database driver allows the majority of BAAN IV s processig to be idepedet of the RDBMS. This chapter provides a overview of the database driver ad a explaatio of how it fits ito the BAAN IV architecture. The followig topics are covered i this chapter: The BAAN IV architecture Data flow through the BAAN IV architecture BAAN IV hardware cofiguratios Level 1 ad Level 2 database drivers The BAAN IV architecture BAAN IV supports a three-tier architecture that cosists of a display tier, a applicatio tier, ad a database tier. The display tier provides presetatio services for user iteractio. The applicatio tier cosists of the BAAN IV applicatio virtual machie ad the applicatio objects. The database tier icludes the BAAN IV database driver ad a third party RDBMS product that acts as the database server. Figure 1 depicts the BAAN IV architecture. The emphasis of this documet is the BAAN IV database driver. The database driver is the iterface betwee the BAAN IV applicatios ad the RDBMS server. The database driver traslates database requests from the BAAN IV applicatio virtual machie to RDBMS-specific SQL requests that it seds to the database server. After the database server retrieves the requested iformatio, the database driver the passes the data back to the BAAN IV applicatio virtual machie. 1-1

10 BAAN IV database driver overview To put the fuctios of the database driver ito perspective, each of the three tiers of the total BAAN IV architecture is briefly described below. Display Driver Display Tier Applicatio Virtual Machie (bshell) Applicatio Objects Applicatio Tier Database Driver Database Server (RDBMS) Database Tier Figure 1, BAAN IV three-tier architecture Display tier The display tier cosists of the display drivers. The display drivers iclude BA, (the ASCII iterface), BX (the X-Widows iterface for UNIX), BW (the BAAN IV user iterface for Microsoft Widows BW), ad BI (for Iteret browsers). The display driver facilitates the commuicatio betwee the user ad the applicatio tier. Data iput from the user through BW or BI is relayed to the BAAN IV applicatio virtual machie; data retured from the BAAN IV applicatio virtual machie is displayed to the user i graphical form by the display server. 1-2

11 BAAN IV database driver overview Applicatio tier The applicatio tier icludes the applicatio objects ad the BAAN IV applicatio virtual machie. Together, the applicatio objects ad the applicatio virtual machie provide much of the fuctioality of BAAN IV. The applicatio objects iclude the compiled BAAN IV applicatios ad the data dictioary. The BAAN IV applicatios provide the fuctioality eeded to implemet the BAAN IV Eterprise Resource Plaig (ERP) system. These applicatios are writte i Baa 3GL or Baa 4GL, which are programmig laguages supported by the BAAN IV Tools package. The data dictioary defies the data models used by the applicatios ad icludes iformatio about the domais, schemas, ad referetial itegrity rules used by BAAN IV. The BAAN IV applicatio virtual machie schedules ad rus the applicatio objects, seds ad receives iformatio to ad from the display server, ad, as ecessary, iitiates a istace of the database driver for commuicatio with the database server. A ruig database driver ca support multiple coectios to a sigle RDBMS istace. If a BAAN IV istallatio stores data tables i multiple RDBMS products or istaces, the applicatio virtual machie must start oe istace of the database driver for each RDBMS product or RDBMS istace with which it must commuicate. The BAAN IV applicatio virtual machie has traditioally bee called the BAAN IV shell or simply the bshell. Throughout the remaider of this documet, the bshell is referred to as the BAAN IV applicatio virtual machie or the applicatio virtual machie. Database tier The database tier cosists of the BAAN IV database driver ad the database server. The database driver provides a commo iterface betwee the BAAN IV applicatio virtual machie ad the database server. Commuicatio betwee the applicatio virtual machie ad the database driver is the same, regardless of which RDBMS product is used as the database server. Oe database driver exists for each of the RDBMS products that BAAN IV supports. Commuicatio betwee the database driver ad the database server is tailored to the RDBMS beig used. The database driver commuicates with the RDBMS through structured query laguage (SQL) statemets ad the ative applicatio programmig iterface (API) of the RDBMS. 1-3

12 BAAN IV database driver overview The database server cosists of Baa Base, the Baa ISAM database, or oe of five third party RDBMS products: Oracle, Iformix, Sybase, DB2, or Microsoft SQL Server. All BAAN IV applicatio data is stored i a relatioal database maaged by a RDBMS. Multiple RDBMS products ca exist i oe BAAN IV istallatio with some data residig i oe database server ad other data residig i aother. Data flow through the BAAN IV architecture The database driver provides a iterface betwee the BAAN IV applicatio virtual machie ad the specific RDBMS server beig used. The flow of data through the system is described below. Whe you perform a operatio at a GUI workstatio, the display server iterprets your iput ad seds the iformatio to the BAAN IV applicatio virtual machie. Based o the iformatio it receives, the applicatio virtual machie rus the appropriate applicatio object. Whe a ruig applicatio object requires iformatio that is stored i the database, the applicatio virtual machie seds the request to the database driver. Data requests from the cliet applicatios are RDBMS idepedet ad are made BAAN IV SQL, a RDBMS-idepedet SQL laguage. Whe the applicatio virtual machie carries out a database query from a applicatio object, it first determies whether or ot a ruig database driver is available to process the query. If o database driver is ruig, or if the ruig database driver istaces are commuicatig with a database server other tha the oe that stores the eeded data, the applicatio virtual machie starts a ew istace of the database driver. The applicatio virtual machie parses the BAAN IV SQL database query it receives from the applicatio object ad seds a iteral represetatio of the query to the database driver. The iteral represetatio of the query that the database driver receives is still RDBMS idepedet. The database driver traslates the database query ito a appropriate query usig SQL statemets compatible with the specific RDBMS beig used. Each database driver takes advatage of the desig of the particular RDBMS that it supports so that the resultig SQL statemets are valid for the RDBMS ad provide the best possible performace. The RDBMS-specific SQL statemets are the submitted to the RDBMS server, which processes the data request. 1-4

13 BAAN IV database driver overview Whe the has processed the query, RDBMS returs the data to the database driver. Error coditios are caught ad hadled by the database driver. The database driver the returs the data ad status iformatio to the applicatio virtual machie, where it provides the iformatio to the applicatio that requested it. The applicatio virtual machie ca also sed a message to the display server, which displays a appropriate message o the user s workstatio. BAAN IV hardware cofiguratios A BAAN IV implemetatio supports several hardware cofiguratios. These cofiguratios iclude stad-aloe mode ad may variatios of cliet/server mode. Available hardware, data storage requiremets, ad performace expectatios determie the most appropriate hardware cofiguratio. Stad-aloe mode refers to a cofiguratio i which all compoets of the BAAN IV architecture ru o a sigle machie. I stad-aloe mode, a ed user ca work from the host. The stad-aloe mode cofiguratio is illustrated i Figure 2. Display Driver Applicatio Virtual Machie (bshell) Applicatio Objects Database Driver Database Server (RDBMS) Figure 2, Stadaloe mode cofiguratio 1-5

14 BAAN IV database driver overview I a cliet/server cofiguratio, the compoets of the BAAN IV architecture are distributed over two or more machies. May cliet/server cofiguratios exists, ad the most commo cofiguratios are described here. The simplest cliet/server cofiguratio is sometimes thought of as a variatio of stad-aloe mode. I this cofiguratio, the applicatio tier, database driver ad RDBMS are o oe machie, whereas the display drivers are distributed amog the user workstatios. A istace of the applicatio virtual machie ad at least oe istace of the database driver is started for each user. All users have access to the same applicatio objects ad database servers. This cofiguratio is illustrated i Figure 3. Display Driver Display Driver Applicatio Virtual Machie (bshell) Applicatio Objects Applicatio Virtual Machie (bshell) Database Driver Database Driver Database Server (RDBMS) Figure 3, Cliet/Server cofiguratio I 1-6

15 BAAN IV database driver overview Whe two machies are available to be used as servers, two cofiguratios are commoly used. I both cofiguratios, the display drivers reside o the user workstatios. I the first cofiguratio, the applicatio tier is placed o oe server, whereas the database driver ad the database server are placed o aother. As with the previous cofiguratio, a istace of the applicatio virtual machie ad at least oe istace of the database driver are started for each user. All users have access to the same applicatio objects ad database servers. This cliet/server cofiguratio is illustrated i Figure 4. This cofiguratio uses the BAAN IV method of cliet/server access betwee the applicatio virtual machie ad the database server. Display Driver Display Driver Applicatio Virtual Machie (bshell) Applicatio Objects Applicatio Virtual Machie (bshell) Database Driver Database Driver Database Server (RDBMS) Figure 4, Cliet/Server cofiguratio II 1-7

16 BAAN IV database driver overview A alterative cofiguratio with two servers is to place the applicatios ad the database driver o oe server ad the database server o aother. Ed user workstatios are agai liked to the machie with the applicatio virtual machie. Agai, a istace of the applicatio virtual machie ad at least oe istace of the database driver is started for each user. All users have access to the same applicatio objects ad database servers. This cliet/server cofiguratio is illustrated i Figure 5. This cofiguratio focuses the RDBMS s ability to provide cliet/server access. Display Driver Display Driver Applicatio Virtual Machie (bshell) Applicatio Objects Applicatio Virtual Machie (bshell) Database Driver Database Driver Database Server (RDBMS) Figure 5, Cliet/Server cofiguratio III May other cofiguratios of cliet/server systems exist: for example, dividig the applicatio logic amog multiple servers or usig multiple servers for distributig the database. 1-8

17 BAAN IV database driver overview Level 1 ad Level 2 database drivers BAAN IV database drivers ca commuicate with the RDBMS server i two modes: Level 1 ad Level 2. With these two modes, there are differeces both i the way the BAAN IV SQL queries are processed ad i the way the data is stored i the database. For BAAN IV, Level 1 drivers are available for all supported RDBMS products. A Level 2 driver is available with BAAN IV for Oracle ad will be available for other RDBMS products i future releases. With a Level 1 database driver, queries to the database oly process a sigle row of a sigle database table at a time. Whe a complex query requires data from multiple tables, it must be broke ito multiple sigle table/sigle row queries. The database driver the jois the combied data before returig the resultig iformatio to the applicatio. Applicatio programs desiged for a Level 1 database driver usually access data oe record at a time. This type of access maps well to the Level 1 sigle table/sigle row queries. To provide good system performace for sigle table/sigle row queries, a extra colum, called a hash colum, is created for each idex defied i the table. This process is called hash optimizatio ad is used to simplify the SQL statemets set to the database server so that the RDBMS optimizer ca process the statemets more efficietly. A Level 2 database driver seds more complex queries to the database server, requires the RDBMS to do more of the work. A applicatio program writte for a Level 2 database driver typically uses set-orieted database access. The Level 2 database driver ca process these more complex queries more efficietly tha a Level 1 driver. I additio, a Level 2 driver does ot use the hash colums that are added whe usig a Level 1 driver with hash optimizatio, so less space is eeded to store the database. A Level 2 database driver typically improves system performace whe the applicatio programs are desiged with set-orieted database access. If a applicatio is writte with record-at-a-time database access, the database queries are very simple. Applicatios with complex database queries ofte show performace gais whe they ru with a Level 2 driver. However, record-at-atime applicatios ca perform poorly with a Level 2 driver because o hash optimizatio exists. You ca migrate betwee a Level 1 ad a Level 2 database driver usig the BAAN IV utilities bdbpre ad bdbpost. The process requires all database tables to be chaged to either add or remove the hash colums. While this is operatio is ot difficult, it could be quite time cosumig, depedig o the quatity of data that eeds to be coverted. 1-9

18 BAAN IV database driver overview 1-10

19 2 BAAN IV database orgaizatio All of the applicatio data used by BAAN IV is stored i database tables i the RDBMS. To keep the majority of the BAAN IV processig idepedet of the RDBMS, BAAN IV uses a data dictioary. The data dictioary icludes domai, schema, ad referetial itegrity iformatio that is stored i a databaseidepedet maer. Because so may tables are eeded, a covetio is used to ame tables, colums withi tables, ad idexes to data withi the tables. This chapter describes the data dictioary ad the amig covetios used by the BAAN IV database drivers to access data stored i the RDBMS. This chapter also discusses how BAAN IV data types are mapped to Oracle data types. The followig topics are covered i this chapter: BAAN IV data dictioary Table amig covetio Colum amig covetio Idex amig covetio Data type mappig Additioal costraits BAAN IV data dictioary A data dictioary is a catalog that provides iformatio about the data i a database. You ca thik of a data dictioary as metadata, that is, data about the data. Use a data dictioary to fid data that resides withi a database table. The BAAN IV database drivers maitai a data dictioary because the data used by the BAAN IV applicatios ca differ from the database tables defied i the RDBMS. The BAAN IV data dictioary maps BAAN IV data types, domais, schemas, ad referetial itegrity iformatio to the appropriate iformatio i the RDBMS. Whe storig or retrievig data i the RDBMS, the database driver maps data dictioary iformatio to database table defiitios. BAAN IV data dictioary iformatio ca be kept i shared memory where it will be available to all ruig BAAN IV applicatio virtual machies. The data dictioary iformatio is shared amog all the sessios ope withi a sigle database driver. 2-1

20 BAAN IV database orgaizatio The BAAN IV data dictioary caot be used directly by the database driver to create Oracle tables because ot all BAAN IV data types exactly match Oracle data types. To create valid Oracle tables, the driver must perform some mappig or traslatio. To map the BAAN IV data dictioary with tables i Oracle, the table ames, colum ames, ad idex ames adhere to set covetios. Table amig covetio The table ame of a BAAN IV table stored i Oracle has the followig format. T <DD Table ame>< Compay umber> The followig describes each of the compoets of the table ame. DD table ame The ame of the table used i the data dictioary. This ame cosists of a package desigatio, a module desigatio, ad a table umber as follows: <DD Table ame> = <package><module><table umber> Package A two-letter code that refers to the BAAN IV package that created the table. For example, a table created by the BAAN IV Tools package has the package code tt. Module A three-letter code that refers to the BAAN IV module withi the package that created the table. For example, a table created by the BAAN IV Distributio Sales module has the module code sls. Table umber A three-digit code that refers to a table that belogs to a BAAN IV module. Compay Number Three-digit umbers used to differetiate areas of fuctioality withi BAAN IV. A compay with the umber 000 must exist. I additio, several other compay umbers ca exist. For example, the data dictioary table ttadv999 with compay umber 000 is created i Oracle as tttadv

21 BAAN IV database orgaizatio Colum amig covetio Each colum i the BAAN IV data dictioary correspods to oe or more colums i a Oracle table. The rules for colum ames are as follows: Geeral Whe a BAAN IV colum ame is created i Oracle, it is preceded by the strig t$. For example, the BAAN IV colum with the ame cpac is created i Oracle with the ame t$cpac. By precedig colum ames by t$, reserved words are avoided. If a colum ame cotais a period [. ], the period is replaced by the dollar character [ $ ]. Log strig colums BAAN IV colums of type strig ca exceed the maximum legth of character colums i Oracle. The Oracle data type CHAR has a limit of 255 characters. Whe a BAAN IV strig colum exceeds this limit, the colum is split ito segmets with up to 255 characters each. The first 255 characters are placed i a colum where the ame of the colum is followed with #1. The ext 255 characters are placed i a colum with a ame followed by #2, ad so o util all the characters of the strig are placed i a colum. For example, if a BAAN IV strig colum called desc cotais 300 characters, the followig two Oracle colums are created: t$desc#1: size 255 t$desc#2: size 45 Array colums I the BAAN IV data dictioary, array colums ca be defied. A array colum is a colum with multiple elemets. The umber of elemets is called the depth. For example, a colum that cotais a date ca be defied as a array of three elemets: a day, a moth, ad a year. I Oracle, the three elemets of the array colum are placed i separate colums. The ames of these colums iclude a suffix with the elemet umber. For example, a array colum called date will become: t$date$1: elemet 1 t$date$2: elemet 2 t$date$3: elemet 3 Note that if the elemet is of type strig ad oe elemet type exceeds the maximum Oracle character size of 255, the elemet is split. For example: t$str$1#1: elemet 1, part 1 t$str$1#2: elemet 1, part 2 2-3

22 BAAN IV database orgaizatio Array compressio The maximum umber of Oracle colums is 254. If the umber of BAAN IV colums exceeds the maximum umber of Oracle colums, the database driver tries to compress (joi) array colums to reduce the umber of colums. All array elemets of oe array colum are stored as oe colum i the Oracle database with the elemets cocateated i a biary format (Oracle data type RAW). The driver starts by compressig the array colum that yields the highest umber of colums ad cotiues compressig array colums util the umber of colums is less tha 254. The ame of the compressed colum i Oracle follows the same covetio used for the other colums. For example: t$array cotais all elemets of the compressed colum. Note that whe a compressed array colum is loger tha 255 characters, it is to be split i segmets of 255 characters or less. Idex amig covetio BAAN IV idexes are idetified by a sequece umber for each table, with the sequece umbers startig at 1. Each table has at least oe idex: the primary idex. Oracle requires that for each user, all idex ames must be uique. For this reaso, the table ame, idex umber, ad the idex type are icluded i the idex ame. For a descedig idex, the character d is appeded to the ed of the idex ame. Idex ames have the followig format: t<dd Table ame><compay umber>$idx<idex umber>[d] For example, the idex ame for a BAAN IV table with ame ttadv999, idex umber 1, compay umber 000, ad idex type ascedig order is: tttadv999000$idx1 If a BAAN IV idex is defied as a uique idex, the the Oracle idex is created with the UNIQUE clause. Without the UNIQUE clause, duplicate idexes are created. Idex ame covetios are used by the Oracle driver whe you create ad delete idexes. Idex ames are used for geeratig idex hits to help the Oracle cost based optimizer (CBO) choose the right executio pla. 2-4

23 BAAN IV database orgaizatio Data type mappig The followig table shows the mappig betwee BAAN IV data types ad their Oracle couterparts. Mappig betwee BAAN IV ad Oracle data types BAAN IV data type Oracle data type Byte NUMBER Eumerated NUMBER Iteger NUMBER Log NUMBER Text NUMBER (Bit)Set NUMBER Float NUMBER Double NUMBER Strig CHAR()/VARCHAR2() Multibyte strig CHAR()/VARCHAR2() Date DATE Note that the BAAN IV Oracle driver i Level 2 mode uses the Oracle CHAR data type because ANSI-compliat behavior is expected for character data, such as with the BAAN IV strig type. Sice BAAN IV SQL expects ANSI-compliat strig compariso sematics, the Oracle CHAR data type is used istead of VARCHAR2. This Oracle data type is used because a BAAN IV strig data type has characteristics that coform to the ANSI specificatio for character data. Whe the CHAR data type is used, operatios such as compariso ad cocateatio ca be performed i a predefied maer with predictable results. Whe the BAAN IV Oracle driver operates i Level 1 mode, the Oracle VARCHAR2 data type ca be used. All ANSI-compliat comparisos will be performed by the driver; oly sigle table sigle row queries are set to the Oracle server. 2-5

24 BAAN IV database orgaizatio Additioal costraits I additio to the above amig covetios ad data types, the followig rules apply whe mappig BAAN IV data to Oracle data: All ames geerated by the database driver are i lowercase characters ad are ot eclosed withi double quotatio marks. This structure meas that Oracle coverts these ames to upper case whe storig them i the Oracle dictioary. Whe ames are retrieved from the Oracle dictioary, they appear i upper case. All colums created by the BAAN IV Oracle driver have the NOT NULL costrait. BAAN IV applicatios do ot support NULLS. The date rage for the BAAN IV applicatio virtual machie is ot the same as the rage for Oracle (Oracle is more restrictive), so some BAAN IV dates are ot valid whe stored with the BAAN IV Oracle driver. The resource variable ora_date determies the date rage used by BAAN IV. For detailed iformatio o the date rage, see Appedix A. 2-6

25 3 Database driver iteral processig The BAAN IV Oracle database driver coverts RDBMS-idepedet database requests ito requests desiged specifically for Oracle. This chapter describes some of the iteral processig that occurs withi the BAAN IV Oracle database driver. First, some of the features that esure data itegrity are discussed. Next, the iteral processig of a SQL statemet withi the driver is explaied. The fial sectio of this chapter describes the mechaisms that allow the default behavior of the database driver to be modified. I this chapter, the followig BAAN IV Oracle database driver iteral issues are discussed. Data itegrity Database driver SQL processig Settig driver behavior Data itegrity Several features of the BAAN IV database driver help to isure data itegrity. These features iclude lockig mechaisms, methods used for isurig referetial itegrity, ad methods used for distributed databases. I additio, data itegrity is maitaied while miimizig etwork traffic by usig data bufferig techiques. This sectio gives a overview of the features used by the BAAN IV Oracle database driver to esure referetial itegrity, to work with distributed databases, ad to apply data bufferig techiques. Lockig strategies are discussed i detail i Chapter 6. Referetial itegrity Referetial itegrity preserves the defied relatioships betwee tables whe records are maitaied. The BAAN IV database driver has a built-i mechaism for preservig referetial itegrity, so it does ot deped o the uderlyig RDBMS. 3-1

26 Database driver iteral processig Distributed databases A BAAN IV SQL query ca require iformatio from multiple tables. Whe tables are distributed, they ca be physically located i differet databases. To access data from distributed tables, the query is split ito multiple queries, with oe query for each database. To service each of these queries, the applicatio virtual machie activates multiple database drivers. Oe active database driver is called upo to retrieve the data required from a sigle database. Whe all of the data required by the origial query is gathered from the databases, the database driver jois the data ad returs it to the applicatio virtual machie. Data bufferig Updates ca be buffered by the applicatio virtual machie ad flushed at the time of trasactio commit or earlier, if ecessary. This procedure reduces the umber of etwork roud trips ad data volumes. Whe multiple rows are retured from a query, the rows are buffered ad the set back to the applicatio virtual machie as oe block. Data reductio ad compressio is applied to miimize the amout of data trasferred betwee the applicatio virtual machie ad the database driver. Database driver SQL processig As discussed i Chapter 1, the applicatio virtual machie seds RDBMSidepedet database queries ad update requests to the database driver. The database driver decides whether or ot to covert these RDBMS idepedet database requests ito SQL statemets that are appropriate to the specific RDBMS beig used. This sectio details the SQL processig performed by the BAAN IV Oracle database driver. Because the BAAN IV database driver uses Oracle Call Iterface (OCI) to commuicate with Oracle, OCI will be described first. The Oracle call iterface (OCI) OCI is a applicatio programmig iterface (API) used to commuicate with the database server. This iterface cosists of a fuctio library that ca be called from a applicatio program to carry out SQL statemets ad commuicate with the data source. 3-2

27 Database driver iteral processig The OCI fuctios called by the BAAN IV Oracle database driver perform the followig actios: Coect to Oracle (ope sessio) Allocate cursors Parse a SQL statemet Bid iput variables Defie output variables Ru a SQL statemet Fetch the resultig rows Commit or abort a trasactio Close, ubid, ad drop a cursor Discoect from Oracle (close sessio) The BAAN IV Oracle driver also uses the followig features of OCI: Array fetches (whe eabled) Array iserts (whe eabled ad possible) SQL processig SQL statemets are dyamically geerated by the database depedet layer of the BAAN IV Oracle database driver. Because BAAN IV applicatios are dyamic, you will ot kow which tables will be used at ru time; therefore, queries caot be prepared before ru time. Withi the BAAN IV Oracle database driver, SQL statemets are processed i several steps: 1 If the BAAN IV Oracle driver receives a query from the applicatio virtual machie, the query is traslated ito a format suitable for Oracle. 2 The query is trasferred to Oracle usig OCI fuctio calls. 3 Withi the BAAN IV Oracle database driver, a Oracle cursor is allocated, ad the query is assiged to the cursor. 4 The SQL statemet is parsed, iput ad output variables are boud ad the query is executed usig the cursor. 5 After the query is executed, a fetch operatio is performed ad the resultig colum values are placed i the boud, output variables. 6 The rows retured by Oracle are passed to the database idepedet layer of the BAAN IV Oracle database driver, which seds the results back to the applicatio virtual machie. 3-3

28 Database driver iteral processig NOTE Whe a statemet eeds to be re-executed, the cursor from the previous ru is closed ad the resultig rows are discarded (whether the re-executio is with the same iput parameters or ot). If ew iput values are required, the ew values are assiged to the iput parameter colums, ad the query is re-executed. However, for re-executio, o reparsig of the statemet or re-bid of iput ad output parameters is required, which improves the overall performace. Whe array fetchig is eabled, multiple rows are fetched i oe call to the driver. Space is allocated withi the driver to buffer multiple rows fetched i oe operatio. Multiple rows ca be fetched to the buffer; ad they are retured to the applicatio virtual machie whe requested. Whe o rows are left i the buffer ad more rows are requested, aother array fetch operatio is carried out. Iserts ca also be buffered. Whe array isertig is eabled, the driver places the rows to be iserted i a buffer. Whe the buffer is full, or whe some other evet ecessitates it, the rows are flushed to Oracle. The rows i the buffer are iserted with a multi row isert. Data ca be maually placed ito the database usig the BAAN IV utility bdbpost6.1. This utility is used to place data ito a ew database table or to apped data to a existig database table. Certai optios ca be set whe usig bdbpost6.1 (see the BAAN IV Tools Techical Maual). Whe bdbpost6.1 is used with the -f optio, the rows are buffered by default ad are flushed whe the array buffer is full. The array size eeds to be specified; otherwise, bufferig is ot performed. The array buffer size ca be specified i the tabledef file o a per-table basis or o a global scale, by usig a eviromet variable. The eviromet variables, resource variables, ad storage file are explaied below. The tabledef file is briefly described i the sectio o eviromet variables. To set driver behavior Several facilities are available to cofigure the BAAN IV Oracle database driver. The most commo facility is through driver resources. Two other facilities for cofigurig the BAAN IV Oracle database driver are eviromet variables ad the storage file. The driver resources ad eviromet variables are described i more detail i Appedix A ad the storage file i Appedix B. 3-4

29 Database driver iteral processig Driver resources The driver resources are parameters that ca be set to modify the behavior of the BAAN IV Oracle database driver. These parameters are set i a file called the resource file (db_resource). Oe resource file exists for all database drivers that ru i a BAAN IV eviromet, ad resources for all the database driver types ca be foud there. A database driver reads the parameters set i the resource file whe it is first ivoked. The resource file may cotai may etries, with oe etry per lie. Each etry is used to set a sigle resource parameter, with the resource ame followed by a colo ad the the value to which the resource is to be set. The followig is a example of the cotets of a resource file that cotais two etries: dbsiit:01 ora_timeout:{0,5,10,15,0} Whe modifyig the behavior of the database driver, you might eed to modify the behavior of the BAAN IV applicatio virtual machie to take advatage of the characteristics of the database driver. Therefore, there are two types of database driver resources exist: those that are used to modify the behavior of the database driver ad those that are used to modify the behavior of the applicatio virtual machie. Driver resources that are used to modify database driver behavior are resources for the server. Driver resources that are used to modify behavior i the applicatio virtual machie are resources for the cliet. I a Widows NT eviromet, the resource file db_resource is located i the directory %BSE%\lib\defaults, where %BSE% refers to the directory i which the BAAN IV software eviromet is istalled. I a UNIX eviromet, the resource file is located i the directory $BSE/lib/defaults where $BSE refers to the directory i which the BAAN IV software eviromet is istalled. If both the database driver ad the applicatio virtual machie ru o the same machie, oly oe db_resource file exists which cotais all the ecessary resource parameters. If the database driver ad the applicatio virtual machie ru o differet machies, oe db_resource file must be located o the machie that rus database driver that cotais the server resources, ad oe db_resource file must be located o the machie that rus the applicatio virtual machie that cotais the cliet resources. I additio to the default resource file db_resource, you ca set up a alterative resource file to override resource values for specific users or groups of users. The alterative resource file is specified with the eviromet variables USR_DBS_RES ad USR_DBC_RES. 3-5

30 Database driver iteral processig Use USR_DBS_RES to specify the path to a file that cotais a alterative resource file for the server. This variable must be set o the machie that rus the database driver. Use USR_DBC_RES to specify the path to a file cotaiig a alterative resource file for the cliet. This variable must be set o the machie that rus the applicatio virtual machie. Ay driver resource set i the alterative resource file will override the settig of the same driver resource i db_resource. The ext sectio describes how to set the database driver eviromet variables. Eviromet variables Eviromet variables ca be used to override driver resources. Usually, a default set of resource parameters is cofigured i the resource file. The admiistrator ca override these default settigs with eviromet variables. For the most part, a eviromet variable correspods to each resource parameter. The eviromet variable ame is usually the uppercase equivalet of the resource parameter ame. As with the database driver resources, some eviromet variables are used to modify the behavior of the database driver (server) ad some are used to modify the behavior of the applicatio virtual machie (cliet). If a database driver eviromet variable for the server should be used, it must be set o the machie that rus the database driver to override the correspodig driver resource. If a database driver eviromet variable for the cliet should be used, it must be set o the machie that rus the applicatio virtual machie to override the correspodig driver resource. Server eviromet variables Eviromet variables that affect the database driver ca be used to override the driver resources for all tables i a database or for specific tables ad compay umbers withi the database. Three ways exist to set the database driver server eviromet variables: Use the BAAN IV sessios Database Defiitios (ttaad4510m000) ad Tables by Database (ttaad4111m000). Maually modify the BAAN IV tabledef6.1 file. Use the stadard operatig system mechaism for settig eviromet variables. 3-6

31 Database driver iteral processig The BAAN IV Database Defiitios (ttaad4510m000) sessio is the recommeded method to modify database driver behavior. If specific tables ad compaies should be cofigured for access with a specific database driver, the Tables by Database (ttaad411m000) sessio should be used. These sessios causes eviromet variables for a particular database driver to override the defaults set i the resource file ad allow the eviromet variables to be maitaied cetrally. The Database Defiitios (ttaad4510m000) sessio maitais database driver cofiguratio iformatio i a file called tabledef6.1. This file is stored i the directory %BSE%\lib, which resides o the machie where the database driver rus. While you should use the Database Defiitios sessio to maitai this file, advaced users ca modify this file maually. The format of the tabledef6.1 file is as follows: <table ame>:<compay umber>:<driver type>(<eviromet variable>=<value>) If multiple eviromet variables are to be specified for a sigle table ad compay umber, they are listed withi the paretheses ad separated by commas. If all tables or all compaies should be specified, the asterisk (*) is used i place of table ame or compay umber. For example, the followig etry ca be made i the tabledef6.1 file: tccom010:812:ora(oraprof=0.4) I this example, all the queries o table tccom that require at least 0.4 secods are logged i the ORAPROF file. Note that this table is cosidered to have a differet database defiitio from other tables. If a Oracle driver is already ruig but is accessig a differet table, a separate driver will be started for this table. Eviromet variables that appear i the driver specificatios of the tabledef6.1 file are put ito the driver s eviromet before it is ivoked, so they are available to the driver at startup. If the default database driver resources must be modified for specific users, the stadard operatig system method ca be used to set database driver eviromet variables for specific users. These eviromet variables will override the settigs created i the Database Defiitios (ttaad4510m000) sessio for these users. 3-7

32 Database driver iteral processig Cliet eviromet variables You ca use database driver eviromet variables that affect the cliet to override the cliet resources that affect the applicatio virtual machie. These eviromet variables must be set o the machie that rus the applicatio virtual machie ad should be set usig the stadard operatig system methods used for settig eviromet variables. Ay cliet eviromet variables that are used override the equivalet resource variables set for the cliet i the db_resource file. Storage file The storage file provides a way to specify the distributio of table data ad idex data i differet tablespaces. Storage parameters are used by the database driver wheever a DDL statemet such as a create table or create idex statemet is executed. The followig is a example of a etry i the storage file: TABLESPACE baa I this example, the database driver adds the <tablespace> clause to the create statemet durig idex or table creatio. A storage file is defied for each database driver. The storage file for the BAAN IV Oracle database driver is called ora_storage ad is located i the Widows NT directory %BSE%\lib\ora or the UNIX directory $BSE/lib/ora. The format of the storage file is described i detail i Appedix B. 3-8

33 4 Database security The BAAN IV Oracle database driver maitais security by cotrollig user access to the database ad user access to database objects. I a Widows NT eviromet, the BAAN IV database admiistrator (DBA) module allows the DBA to cotrol access to the database usig BAAN IV sessios. Usig the DBA module makes DBA tasks easier ad less proe to errors tha usig database driver tools directly. I a UNIX eviromet, the utility programs ora7_admi6.1 ad ora7_mait6.1 are used i place of the DBA module for Oracle7. For Oracle8, the utilities are ora8_admi6.1 ad ora8_mait6.1. From this poit forward, the utilities are refered to as orax_admi6.1 ad orax_mait6.1. This chapter first discusses how the BAAN IV Oracle database driver hadles issues related to database security. It the briefly describes the DBA module, ad the describes the orax_admi6.1 ad orax_mait6.1 utilities. The followig topics are covered i this chapter: Database security The DBA module The utility programs orax_admi6.1 ad orax_mait6.1 Database security Two aspects of database security exists: object security ad autheticatio. Object security refers to the process of determiig whether or ot a user who has access to the database is authorized to access particular database objects. Autheticatio refers to the process of determiig whether or ot a user is authorized to access the database. Both object security ad autheticatio use the cocept of groups to esure security. This sectio first describes the group cocept, the describes how the BAAN IV Oracle driver provides object security ad autheticatio. 4-1

34 Database security Groups I ay RDBMS, a group is defied as a collectio of database users. All users assiged to a group are grated the same database privileges. Oce a group is defied with a certai set of privileges, users ca be assiged to that group. Usig groups simplifies maagemet of a large umber of groups with commo requiremets. A BAAN IV group cosists of a database ame ad methods for providig object security ad autheticatio withi the database. The BAAN IV group ame is the same as the ame of the database that holds the BAAN IV data withi the RDBMS. The BAAN IV group uses the mechaisms of the RDBMS to provide object security ad autheticatio. A BAAN IV group is a superset of the usual RDBMS group i that it icludes ot oly the RDBMS group, but also the database ame ad a RDBMS logi. I Oracle, a BAAN IV group is made up of three compoets: A database schema. This schema has the same ame as the BAAN IV group. A logi (for autheticatio). This fuctio is the same ame as the BAAN IV group ad is assiged database ower (DBO) privileges i the database. A Oracle role (for object security). This role is created ad becomes the target for privileges grated o objects i the database. Users are associated with the Oracle role ad, as a result, iherit the privileges grated to the Oracle role. The advatage of havig a table assiged to a role is that the members of the group ca share ad operate o the same data i a sigle table. For example, users maria ad joh ca both be assiged to BAAN IV group baadb. Group baadb ows the tables ad grats select, isert, delete, ad update privileges to the Oracle role. As a result, users maria ad joh iherit the select, isert, delete, ad update privileges grated to the Oracle role, which allows them to access ad maipulate BAAN IV group table data. The BAAN IV user is shielded from the RDBMS groups. The database driver does all the processig that is eeded to make use of the RDBMS groups. Oly the database admiistrator eeds to be cocered about the RDBMS groups, ad the BAAN IV DBA module allows the admiistrator to easily maitai the RDBMS groups. 4-2

35 Database security Object security I Oracle, if you create a object such as a table, you become the ower of the object, ad oly you ca access the object. Other users ca oly access the object if they have bee grated privileges to do so. I a BAAN IV eviromet where may users access the same tables i the Oracle database, a mechaism has bee developed to allow users to share these tables. To allow differet BAAN IV users to share the same Oracle table, a group cocept is used. A BAAN IV group maps users to a database i Oracle ad esures that members of the group have sufficiet privileges to access data i the group s tables. The BAAN IV Oracle driver uses a Oracle role to implemet the BAAN IV group cocept. Wheever a ew table is created by the group, the user, select, isert, delete, ad update privileges are grated to the Oracle role. Ay user associated with the role automatically iherits these privileges ad ca idividually perform these operatios o the group table. Whe ew users are added, they oly eed to be associated with a Oracle role because they automatically iherit all privileges curretly grated to the role, which alleviates the eed to grat privileges to the user for every group object i the database. Whe the user is dropped from the role, these privileges are revoked, ad the user o loger has access to tables withi that role. If the privileges to operate o the tables are explicitly grated to the user, the these privileges must also be explicitly revoked whe the user is dropped from the role. The overhead of addig users is greatly reduced by gratig privileges to the role, which also provides flexibility ad ease of maiteace. A user ca defie whether a table should be created as a group table or as a private table. Whe a table is idetified as a private table, the user becomes the ower ad o privileges are give to other users. Whe a table is idetified as a group table, the table is created by the group logi, ad the privileges are grated to the group, which allows all users i the group to access the table. A table ca be cofigured as private or group via the Widows NT file %BSE%\lib\ora\ora_storage or the UNIX file $BSE/lib/ora/ora_storage. I the DDL statemets geerated by the driver, object ames are ot qualified by the ower ame. Owership is determied by the sessio (group or user) i which the create table is ru. Whe creatig objects idetified as belogig to the group, the user who create the object logs o to Oracle as the group user. I this case the table will be owed by the group ad permissios will be grated o it to allow access to all group users. Whe creatig objects idetified as private, users are coected to Oracle uder their ow logi. Whe private objects are created, the user ows them; o other permissios are grated. 4-3

36 Database security A table s cofiguratio is defied i the Widows NT file %BSE%\lib\ora\ora_storage or the UNIX file $BSE/lib/ora/ora_storage. The format is explaied below. The keywords group or private ca be specified i the appropriate field. For example: tdsls:*:t:group:011:: tdsfc:*:t:private:011:: This structure idicates that tables i module tdsls are created as group tables, ad all users have their ow private tables i module tdsfc. Autheticatio The database driver maps BAAN IV users to Oracle user accouts to allow them to establish a coectio to Oracle ad access data. To prevet uauthorized users from accessig the database, omapped users caot establish a coectio to the database. Whe a database is created, a admiistrator creates a logi for the user ad associates the user with a group i the database that has object privileges. The group user correspods to the target database. The members belogig to this group iherit the group privileges ad are able to establish a coectio to the database through either a uified logi or by usig a valid password stored i ecrypted form i the driver admiistratio files. A user ca be added to or dropped from the Oracle role by usig the BAAN IV database admiistratio (DBA) module. Users who are authorized to access the database are registered i the BAAN IV driver admiistratio files. The user ame ad password BAAN IV uses to log o to Oracle o behalf of the user are maitaied i the Widows NT file %BSE%\lib\ora\ora_users or the UNIX file $BSE/lib/ora/ora_users. All the BAAN IV users ad their correspodig Oracle logo ames ad passwords ad the ame of the group to which they are assiged are defied i the Widows NT file %BSE%\lib\ora\ora_users or the UNIX file $BSE/lib/ora/ora_users. The format of each etry i this file is as follows: <BAAN IV user>:<oracle user>:<ecrypted Oracle User password>: <BAAN IV group ame> The BAAN IV Oracle driver is started by the BAAN IV applicatio virtual machie o behalf of the user. From the Widows NT file %BSE%\lib\ora\ora_users or the UNIX file $BSE/lib/ora/ora_users, the driver idetifies the Oracle user ad the user s password ad establishes the coectio to Oracle. 4-4