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Use embedded SQLJ with the DB2 for z/OS Legacy driver

Structured Query Language in Java (SQLJ) is a set of programming extensions that enable a programmer, using the Java programming language, to embed statements that provide Structured Query Language (SQL) database requests. You can use the DB2 for z/OS Legacy driver with the data access applications.

  1. To use SQLJ with WebSphere Application Server for z/OS and the DB2 for z/OS Legacy Driver, install DB2 APAR PQ76442.

  2. Container Managed Persistence (CMP) beans generated using SQLJ are not supported by the DB2 for z/OS Legacy Driver. Use the DB2 Universal Driver for CMPs generated using SQLJ.

Following are the steps required to develop applications with SQLJ that run on WAS for z/OS v6.0 using the DB2 for z/OS Legacy driver.


Tasks

  1. Design the application in Rational Application Developer according to your requirements, using SQLJ when necessary. For example, if you develop a bean called Test that uses BMP, code TestBean.sqlj (instead of TestBean.java).

    1. From your DB2 for z/OS installation, copy the db2sqljclasses.zip file to a directory on your workstation, then modify the Java Build Path of our EJB Java archive (JAR) project to include the db2sqljclasses.zip file.
    2. Translate your SQLJ code according to the following steps:

      1. Locate your SQLJ file, then use ASCII mode transfer to FTP it to an HFS in your z/OS environment.

      2. Use the sqlj command to translate your SQLJ code into Java code. Two files are produced, one with a .java extension and the other with an .ser extension.
        sqlj -compile=false SQLJ_FILE_NAME
        

      3. Use ASCII mode transfer for the .java file and BINARY mode transfer for the .ser file to move these files back to the directory on your workstation where the SQLJ file resides.
      4. Refresh the project.

    3. Generate deployment code for the application.
    4. Export your EAR file.

  2. Install the application

    1. Create a data source with the DB2 for zOS Local JDBC Provider (RRS). When defining the JDBC Provider and data source, the default values are sufficient for providing SQLJ support.

    2. Install the application into WebSphere Application Server.

      Use the data source we created in Step 1 to resolve your resource references.

  3. Customize your serialized profiles When we generate the deployment code, serialized profiles, or files with an .ser extension, specific to the application, are created. These profiles must be customized in a z/OS environment before they can be used.

    1. Use binary transfer to transfer the serialized profiles to the z/OS environment on which we installed your application. Alternatively, use the Java jar command to extract the serialized profiles from the EJB JAR file in your installed EAR directory.

    2. Use the db2profc command to customize your serialized profiles. We can get information about the various options associated with this command from the DB2 documentation; however, here are the minimum requirements to customize your profile:
      db2profc -pgmname=PROGRAM_NAME PROFILE_NAME
      

      • Where:

        • PROGRAM_NAME must be a valid MVS™ PDS member name, and can be up to seven characters.
        • PROFILE_NAME is the name of the serialized profile that we want to customize. Run db2profc one time for each profile.

      • The profile customizer creates four DBRM data sets in the PDS USERNAME.DBRMLIB.DATA. The member names of the DBRMs begin with what we specified as PROGRAM_NAME.

      • Ensure that your CLASSPATH environment variable includes:

        • The location of the serialized profile

        • The EJB JAR file in your installed EAR directory

      • Allocate a PDS to contain the DBRMs created. Name this PDS USERNAME.DBRMLIB.DATA, where USERNAME is the user who implements the db2profc command.

        The following fields are an example:

        Space units=TRACK
        Primary quantity=15
        Secondary quantity=5
        Directory blocks=10
        Record format=FB
        Record length=80
        Block size=27920
        Data set name type=PDS
        

    3. Place the existing serialized profiles, which are now customized, into a location that is part of the application classpath and that is ahead of the serialized profiles that exist in your EJB JAR file.

      The output of the DB2 profile customizer and the input file have the same name. Move the output file ahead of the original serialized profile in the classpath. Alternatively, we can move the customized profile into the EJB JAR file, replacing the original. IBM recommends that we replace the original file.

      IMPORTANT: If we run the db2profc command from the directory where the serialized profile exists, the profile customizer overwrites the serialized profile. Because we need only the customized version after the profile customizer has run, this is not a problem.

    4. Bind your DBRMs into a package.

      You must create the database tables before binding your DBRMs. If we do not, the bind job fails.

      The db2profc customization command creates a series of DBRMs that must be bound into packages. For each customized profile, four DBRMs are created.

      These DBRMs:

      • Are located in USERNAME.DBRMLIB.DATA
      • All have names that begin with what we specified as PROGRAM_NAME
      • Are numbered from 1-through-4

        For example, if you log in as IBMUSER, and we specify -pgmname=TESTBMP, then run the db2profc command, the four data sets, TESTBMP1, TESTBMP2, TESTBMP3, AND TESTBMP4 are created and placed in the PDS IBMUSER.DBRMLIB.DATA.

        These data sets must be bound into packages with isolation of UR, CS, RS, and RR. Run a bind for each serialized profile that you customize.

    5. After you bind all of the DBRMs into packages, bind the packages into a plan. Name the plan whatever you like.

      IMPORTANT: You must also include the JDBC packages in the package list (PKLIST) of the new plan. The default names for the JDBC packages to include are DSNJDBC.DSNJDBC1, ..., DSNJDBC.DSNJDBC4. If the installation did not use the default names for the JDBC packages, contact your DB2 administrator to determine the names of the JDBC packages needed to include.

      Following is a sample job used to bind a new plan.

      • One serialized profile was created while logged on as IBMUSER.
      • -pgmname=TESTBMP was specified to run db2profc.

      • The new plan is named SQLJPLAN.

      //BBOOLS  JOB (516B,1025),'IBMUSER',MSGCLASS=H,CLASS=A,PRTY=14,
      //         NOTIFY=&SYSUID,TIME=1440,USER=IBMUSER,PASSWORD=IBMUSER,
      //         MSGLEVEL=(1,1)
      //********************************************************************
      //BINDOLS  EXEC PGM=IKJEFT01,DYNAMNBR=20
      //DBRMLIB  DD  DSN=IBMUSER.DBRMLIB.DATA,DISP=SHR
      //*        DD  DSN=MVSDSOM.DB2710.SDSNDBRM,DISP=SHR
      //SYSTSPRT DD  SYSOUT=*
      //SYSPRINT DD  SYSOUT=*
      //SYSUDUMP DD  SYSOUT=*
      //SYSTSIN  DD  *
      
       DSN SYSTEM(DB2)
      
       BIND -
           PACKAGE(TESTBMP) -
           QUALIFIER(IBMUSER) -
           MEMBER(TESTBMP1) -
           VALIDATE(BIND) -
           ISOLATION(UR) -
           SQLERROR(NOPACKAGE) -
      
       BIND -
           PACKAGE(TESTBMP) -
           QUALIFIER(IBMUSER) -
           MEMBER(TESTBMP2) -
           VALIDATE(BIND) -
           ISOLATION(CS) -
           SQLERROR(NOPACKAGE) -
      
       BIND -
           PACKAGE(TESTBMP) -
           QUALIFIER(IBMUSER) -
           MEMBER(TESTBMP3) -
           VALIDATE(BIND) -
           ISOLATION(RS) -
           SQLERROR(NOPACKAGE) -
      
       BIND -
           PACKAGE(TESTBMP) -
           QUALIFIER(IBMUSER) -
           MEMBER(TESTBMP4) -
           VALIDATE(BIND) -
           ISOLATION(RR) -
           SQLERROR(NOPACKAGE) -
      
      
       BIND PLAN(SQLJPLAN)                 -
        QUALIFIER(IBMUSER)                 -
        PKLIST(TESTBMP.*                   -
               DSNJDBC.*                 ) -
        ACTION(REPLACE) RETAIN             -
        VALIDATE(BIND)
      
      END
      /*
      
    6. Grant the appropriate authority to the new plan. Use an interface to DB2, such as SPUFI, to grant the authority. Issue this command:
      GRANT EXECUTE ON PLAN PLANNAME TO APPSERVERID 
      
      Where:

      • PLANNAME is the name of the plan that you bound.
      • APPSERVERID is the ID under which WebSphere Application Server runs; for example, CBSYMSR1.

  4. Configure your data source to use the new plan

    1. From the WAS for z/OS Administrative Console, navigate to your Data Source and select Custom Properties.

    2. Select the Custom Property planName.
    3. Update the value of planName with what you named your plan when it was bound.

    4. Set enableSQLJ to true.

  5. Stop and restart the server.

  6. Run the application.

  • Deploy SQLJ applications