Feng Cai DB2 System Programmer/ACXIOM

Transcription

1 Platform: DB2 on z/os Nuts and Bolts of JDBC/SQLJ for DB2 UDB on z/os Feng Cai DB2 System Programmer/ACXIOM Session: F8 08:30-09:40 May 25 th 2005 This presentation is intended for application DBAs who support Java application accessing DB2 UDB for z/os. The topic includes installation, configuration, monitoring and troubleshooting. It will also cover application development environment issues and configuration parameters related to db2 in Websphere. The database server is DB2 UDB for z/os, the program is on different platform(uss, Unix, Linux ) It will not discuss how to write Java code accessing db2, Java store procedure is not covered either. 1

2 Agenda Introduction of JDBC Driver Legacy and Universal JDBC driver on USS Legacy and Universal JDBC driver on Linux/Unix/Windows User experience in Java development for DB2 UDB on z/os Websphere datasource configuration and DB2 UDB on z/os 2 2

3 JDBC driver in general Type 1: JDBC-ODBC bridge, no longer been used Type 2: Partly Java, partly native code, database client library is needed Type 3: Pure Java, also called net driver in db2(deprecated) Type 4: Pure Java, can talk directly to database We will only discuss type 2 and type 4 driver SQLJ is static SQL model to complement dynamic SQL(JDBC model). 3 3

4 Legacy JDBC driver Only Type 2 driver is supported JDBC 1.2 with JDK 1.1.x and JDK 1.3 JDBC 2.0 with JDK 1.3 Different driver on different platform RRSAF attachment on USS, DDF connection on LUW Different package for different platform, PTF and fixpack. 4 4

5 Universal Driver Type 2 and Type 4 support, they use the same driver, controlled by URL Type 2 URL: jdbc:db2:dbname Type 4 URL: jdbc:db2://server:port/dbname JDBC 2.0 with JDK 1.3 JDBC 3.0 with JDK 1.4 RRSAF for local connection(uss type 2), DDF for remote connection(all Type 4, LUW type 2) Same package for different platform, PTF and fixpack. 5 5

6 Universal Driver Why Universal Driver Same driver on multiple platforms SQLJ development is easier Message is more clear, legacy driver can only produce jdbc error message in SQLExcption, universal driver can produce DB2Diagnosable and DB2Sqlca. Trace is a lot better (A lot more information in the trace, you can actually understand it, and trace can be controlled by program). New SQL function 6 6

7 Universal Driver Type 2 or Type 4 Type 4 is very easy to manage, no db2 client or catalog, just jar files in CLASSPATH Performance? Type 2 if application and DB2 are on the same machine, Type 4 if they are on different machine. Both use DRDA, type 2 needs going into db2 client which is another layer Our experience shows less than 5% difference between type 4 and type 2 for remote connection. Local connection on z/os means program running on USS, type 2 is faster. (No network time) 7 7

8 Universal Driver Package (V8 CLI package, does not change with fixpack or PTF) 3(default)*4(isolation)*2(hold, nohold) packages and a single static package SYSLH100 SYSLN100 SYSLH101 SYSLN101 SYSLH102 SYSLN102 SYSLH200 SYSLN200 SYSLH201 SYSLN201 SYSLH202 SYSLN202 SYSLH300 SYSLN300 SYSLH301 SYSLN301 SYSLH302 SYSLN302 SYSLH400 SYSLN400 SYSLH401 SYSLN401 SYSLH402 SYSLN402 SYSSTAT Java com.ibm.db2.jcc.db2binder url xxx [ size?] [-collection? ] You can change the size, but chances are you do not need to. If the application complains about sqlcode -805 for SYSLN203, usually it is not closing something. The default Collection ID is NULLID, but you can use your own 8 8

9 Legacy JDBC driver on USS What you need to configure STEPLIB CLASSPATH LIBPATH PATH DB2SQLJPROPERTIES Serialization file Package Plan 9 9

10 Legacy JDBC driver on USS export STEPLIB=DBT5.DB2.SDSNEXIT:DBT5.DB2.SDSNLOD2:DBT5.DB2. SDSNLOAD export CLASSPATH=$CLASSPATH:/db2/dbt5/classes/db2j2classes.zip:/db2/d bt5:/db2/dbt5/classes/db2sqljclasses.zip:/db2/dbt5/classes/ db2jdbcclasses.zip export LIBPATH=$LIBPATH:/db2/dbt5/lib export PATH=$PATH:/db2/dbt5/bin export DB2SQLJPROPERTIES=/db2/dbt5/dbt5.properties 10 10

11 Legacy JDBC driver on USS DSNJDBC_JDBCProfile.ser must in CLASSPATH Package: DSNJDBC.DSNJDBC? IBM provides default DSNJDBC_JDBCProfile.ser and DBRM, bind jobs in SDSNSAMP(DSNTJJCL) Can use db2genjdbc if the default resource is not enough db2genjdbc -statements=??? -calls=??? DSNJDBC Default plan, can be specified in DB2SQLJPROPERTIES 11 11

12 Legacy JDBC driver on USS Java library in HFS, internal code in SDSNLOD2 erwxrwxrwx 1 AUTBASE IA0SYS 8 Nov libdb2os390j2.so-> DSNAQLDA What does e and -> mean It is symbolic link, the real module is in STEPLIB or LINKLIST 12 12

13 Universal Driver in USS (Type 2) What you need to configure for Type 2 Driver STEPLIB CLASSPATH LIBPATH PATH PACKAGE PLAN 13 13

14 Universal Driver in USS (Type 2) export STEPLIB=DBT5.DB2.SDSNEXIT:DBT5.DB2.SDSNLOD2:DBT5.DB2. SDSNLOAD export CLASSPATH=$CLASSPATH:/db2/dbt5/jcc/classes/db2jcc.jar:/db2/dbt5 /jcc/classes/db2jcc_license_cisuz.jar:/db2/dbt5/jcc/classes/sqlj.zip export LIBPATH=$LIBPATH:/db2/dbt5/jcc/lib export PATH=$PATH:/db2/dbt5/jcc/bin 14 14

15 Universal Driver in USS (Type 2) Package: CLI package Do you need a PLAN for type 2 driver? The default is DSNRRSAF, it may show up as?rrsaf in monitor, package list NULLID.* is included. For JDBC program, you do not need one, but for SQLJ program, you probably want to have one or specify package list. If you use SQLJ without specifying plan or package list, you will get this error: DB2 ERROR: -812 IN RTN:Java SQLCODE SQLERRMC -812 CUDC ;DSNRRSAF; 15 15

16 Universal Driver in USS (Type 2) Do you need Properties file? Implicit: propertiesdb2jccconfiguration.properties in CLASSPATH Explicit: java Ddb2.jcc.propertiesFile=??? You can set everything as JVM option Java Ddb2.jcc.planName=??? Ddb2.jcc.pkList=??? 16 16

17 Universal Driver in USS (Type 4) Type 4 driver Only CLASSPATH is needed. Include db2jcc.jar, db2jcc_license_cisuz.jar, sqlj.zip Plan name is DISTSERV, all packages are included. There is a separated product called z/os Application Connectivity to DB2 for z/os and OS/390, it is for LPARs that do not have db2 and is installed into a different directory

18 Legacy driver for LUW Client JDBC driver is part of DB2 for LUW client. $INSTHOME/sqllib/java for JDBC 1.2 $INSTHOME/sqllib/java12 for JDBC 2.0 User runs. $INSTANCE_HOME/sqllib/db2profile to get environment DB2 connect software is needed Only Type 2 is supported Remote databases need to be cataloged Use CLI layer(you can use CLI trace) 18 18

19 Universal Driver for LUW Client Part of V8 DB2 for LUW client $INSTHOME/sqllib/java Support type 2 and type 4 Only Jar files(include license file) and zip files needed for type 4 driver, no db2 client, no database catalog DB2 connect software is not necessary If Type 4 connects to DB2 for z/os directly You need license for each client It can not use db2 connect function(connect concentrator, Data sharing awareness etc) Bypass the CLI layer 19 19

20 Application Development JDBC or SQLJ For mainframe DBAs, they want static SQL. Most java developers come from open system, where JDBC is their choice. For new application for DB2 on z/os, SQLJ is better Performance vs dynamic statement cache for JDBC(parameter marker, any one?) Performance consistency, peace of mind for DBA! Detect error earlier Security Monitor SQLJ code is easier (?) 20 20

21 Application Development JDBC: javac $program.java SQL: sqlj $program.sqlj compile=false Translate step: just like precompile, $program.java and $program_sjprofile0.ser are generated javac $program.java Compile step: if you do not specify compile=false option in sqlj, you do not need to run this step. $program.class is generated. db2sqljcustomize user xxx password xxx url xxx [option] [- bindoption] $program_sjprofile0.ser Customize step: $program_sjprofile0.ser is updated, package is binded into db

22 Application Development SQLJ is a layer on top of JDBC *.ser controls whether the program is running as JDBC or SQLJ SQLJ program can run as JDBC without customization. However, you can force the application to stop or generate a warning message. java -Ddb2.jcc.sqljUncustomizedWarningOrException=? 0 The DB2 Universal JDBC Driver does not generate a Warning or Exception when an uncustomized SQLJ application runs. This is the default. 1 The DB2 Universal JDBC Driver generates a Warning when an uncustomized SQLJ application runs. 2 The DB2 Universal JDBC Driver generates an Exception when an uncustomized SQLJ application runs. Use db2sqljcustomize command to generate package or bind file Use db2sqljprint(db2profp) to check *.ser file

23 Application Development Sample output of uncustomized ser file ->db2sqljprint sample02_sjprofile1.ser printing contents of profile sample02_sjprofile1 created ( ) associated context is sample02ctx profile loader is contains 0 customizations original source file: sample02.sqlj contains 2 entries 23 23

24 Application Development Sample output of customized ser file ->db2sqljprint sample03_sjprofile0.ser printing contents of profile sample03_sjprofile0 created ( ) associated context is sample03ctx profile loader is contains 1 customizations com.ibm.db2.jcc.sqlj.customization@47d825bc original source file: sample03.sqlj contains 2 entries DB2 ProfileData custom data Package Name: SAMPLE0 Package Version: null Package Collection: TESTCOLL Is Default Collection: false Package Consistency Token, hex format: a Package Consistency Token, character format: dbijpbfq 24 24

25 Application Development db2sqljcustomize (db2profc in legacy driver) db2sqljcustomize -user xxxx -password xxxxx -url jdbc:db2://g390:2590/dbt5 -rootpkgname SAMPA collection testcoll -pkgversion JJJ -bindoptions qualifier TEST owner DBAGROUP collection TESTCOLL" sample02_sjprofile0.ser Use type 4 for db2sqljcustomize. This is the only supported connectivity. Some new options in Universal Driver: rootpkgname vs singlepkgname pkgversion 25 25

26 Application Development BINDOPTION and db2sqljcustomize option must match Bindoptions is what is in package, db2sqljcustomize option is what is in *.ser file. Example: If you specify collection on bind option, but not in db2sqljcustomerize option, you will get 805. The default collection in *.ser is NULLID. db2sqljcustomize -user xdbgp -password xxxxx -url jdbc:db2://g390:2590/dbt5 -rootpkgname SAMPA [ collection testcoll] -pkgversion JJJ -bindoptions qualifier TEST owner DBAGROUP collection testcoll" sample02_sjprofile0.ser 26 You can use db2sqljprint to check Collection ID in *.ser file 26

27 Application Development Upgrade db2 driver before DB2 for z/os V8 migration. On USS, please install PQ95284 (JCC driver 2.5) On LUW, please install fixpack 8. You may get SQLCODE 4700(ATTEMPT TO USE NEW FUNCTION BEFORE NEW FUNCTION MODE) with DB2 V8 COMPAT mode from old driver when using db2sqljcustomize

28 Application Development Some user experiences db2sqljcustomize option QUALIFIER = SET CURRENT SQLID? (design change request) Create alias Create Secondary group for Qualifier (Security group unhappy) Disable online checking db2sqljcustomize on Windows does not work very well. We do it on Linux 28 28

29 Application Development Table Qualifier For SQLJ, we do not use table qualifier, just like normal COBOL, C/C++ program that uses embedded static SQL. The qualifier is specified in db2sqljcustomize step. Program will get SQL 204 if not customized. For JDBC, we would like to use qualifier for table. java -DDB2G2SCHEMA=CDBLACCT Java code use System.getProperty("DB2G2SCHEMA") and work with what is returned. Put it in ini file and read from Java by getproperty, you can also put URL, Driver name there so it can be easily changed. Create alias for non qualified table 29 29

30 Application Development Get performance data from program Get connection DB2SystemMonitor monitor=((db2connection)con).getdb2systemmonitor(); monitor.enable(true); monitor.start(com.ibm.db2.jcc.db2systemmonitor.reset_times); Application code.. monitor.stop(); System.out.println(monitor.getServerTimeMicros()); System.out.println(monitor.getNetworkIOTimeMicros()); System.out.println(monitor.getCoreDriverTimeMicros()); System.out.println(monitor.getApplicationTimeMillis()); 30 30

31 Websphere and DB2 V4 WAS database Session database for Websphere clustering V5 No WAS database, Websphere configuration now use XML Session database is recommended but not a must for clustering Web interface for administration, no fat client 31 31

32 Websphere and DB2 Websphere use datasource, datasource configuration includes driver type, CLASSPATH, ID and password, connection pooling (V5) To make sure all configurations related to datasource are correct, ask Websphere admin to give you read access for admin site

33 Websphere and DB2 Connection Timeout : Interval, in seconds, after which a connection request times out and a ConnectionWaitTimeoutException is thrown. Max Connections Min Connections Reap Time: 180 Interval, in seconds, between runs of the pool maintenance thread. Unused Timeout: 300 Interval, in seconds, after which an unused connection is discarded by the pool maintenance thread. Aged Timeout: 0 Interval, in seconds, after which an unused, aged connection is discarded (regardless of recent usage activity) by the pool maintenance thread. Purge Policy: EntirePool Specifies how to purge connections when a "stale connection" or "fatal connection error" is detected

34 Websphere and DB2 Some user experiences: We run Websphere V5 on zlinux, Linux on Intel and AIX, use type 4 driver. Min connection set to 0 in Websphere if IDTHTOIN is set in DDF, unused timeout should be less that IDTHTOIN. Let Websphere kill the connection in the pool instead of db2. Websphere folks always ask for high number of max connection. Our experience shows that when we hit the limit, it is usually an application problem. There is no reason to allow too many DDF connections

35 Nuts and Bolts of JDBC/DB2 for DB2 UDB on z/os Session: F8 Feng Cai ACXIOM Corp 35 35