This tutorial shows how to execute DB2 statements from within a DSNREXX procedure. This is done by creating a JCL project and then associating it with an XA resource, enabling you to run a DSNREXX procedure using sample JCL provided with
Visual COBOL.
Note: You need to ensure that you consistently use 32-bit versions of the tools and utilities as you proceed through this tutorial.
Prerequisites
To complete this tutorial, you need the following software in addition to
Visual COBOL:
- IBM's DB2 Database for Linux, UNIX, and Windows (LUW). See
Additional Software Requirements on Windows for more information.
Creating a DB2 LUW sample database
If you do not already have a sample database you will need to create one. You can create a sample database by running the
db2sampl utility. The utility is part of the DB2 installation:
- Start a command prompt as an administrator.
- Type
db2sampl -sql
- To verify that the database can be connected to, start a DB2 Command Window.
- Type
DB2 CONNECT TO SAMPLE USER
user-id USING
password
You are presented with database connection information, for example:
Database Connection Information
Database server = DB2/NT64 11.1.0
SQL authorization ID = user-id
Local database alias = SAMPLE
Note: See the DB2 LUW documentation for more information on how to create or catalog the SAMPLE database. Click
Start, and type
DB2 Information Center. Choose
DB2 Information Center, and search for "Create Sample database" or "Catalog database" as required.
Catalog the sample database as an ODBC data source
If your sample database has not been cataloged as an ODBC data source, then perform the following steps:
- Click
Start or use the shortcut keys
Ctrl+Esc. In the search field, type
ODBC.
- In the results list, select
ODBC Data Source Administrator (32-bit) or
ODBC Data Sources (32-bit), depending on your version of Windows.
This opens the 32-bit version of the
ODBC Data Source Administrator tool.
- Click
System DSN tab.
- Click
Add.
This opens the
Create New Data Source dialog box.
- Click
IBM DB2 ODBC DRIVER.
- Click
Finish.
This opens the
ODBC IBM DB2 Driver - Add dialog box.
- In the
Data source name field, type
SAMPLE
- In the
Database alias list, select the
SAMPLE database.
- Optionally, in the
Description field, type a description for your data source.
- Click
OK, and then click
OK.
Create an ODBC XA switch module
If you have not already created the ODBC XA switch module, perform the following steps:
Note: To build the ODBC XA switch module, you must have the Windows Software Development Kit (SDK) installed for your version of Windows. Before building the switch module, ensure that your LIB environment variable contains the path to your Windows SDK LIB directory.
- Start an
Visual COBOL command prompt (32-bit) as administrator.
- Change to the
%ProgramFiles(x86)%\Micro Focus\Visual COBOL\src\enterpriseserver\xa
directory.
- Enter
build odbc
Note: Make a note of the switch module name created, it is used in subsequent steps.
Create the project's workspace
- Create the working directory on your machine, for example
C:\User\Public\REXXSAMPLE
Import the sample MSS project
To import the sample Mainframe Subsystem (MSS) project:
- Start
Visual COBOL for Eclipse.
- When prompted for a workspace, specify the path created above
C:\Users\Public\REXXSAMPLE
- Click
OK.
- On the
Welcome page, click
Open Team Developer Perspective.
- Click
.
This opens the
Import dialog box.
- Expand
General, and click
Existing Projects into Workspace.
- Click
Next.
- On the
Import Projects page, click
Browse next to
Select root directory.
- Choose
%PUBLIC%\Documents\Micro Focus\Visual COBOL\Samples\Mainframe\SQL\OpenESQL\DSNREXX\Test1
- Click
OK.
- In the
Projects list, check
Test1.
- Check
Copy projects into workspace.
- Click
Finish.
Create an MSS-enabled
COBOL Server
Now you want to create an
enterprise server region with MSS for JCL use:
- In
Application Explorer view, right-click the
Test1 project.
- Click
.
This opens the
New Enterprise Server dialog box.
Note: If you are prompted with an
Enterprise Server Sign On dialog box, click
OK without specifying any sign-on details. This is a standard security dialog box. Also, if prompted to disable password recovery, click
No.
- In the
Name field, type
REXX32
- Click
Browse next to the
Template field.
- In the
Select template file dialog box, click
JCLTemplate.
- Click
Open.
- In the
Associate with projects field, check
Test1.
- Click
Finish.
Add an XA resource for REXX procedures pointing to the DB2 LUW SAMPLE database
Now that the
enterprise server region is created, you need to set up an XA resource:
- In Server Explorer, right-click
Local [localhost:86].
- Click
Open Administration Page.
- Click
Edit next to the REXX32 region name.
- Click
.
- Click
Add.
- In the
ID field, type
DB2T
- In the
Name field, type
REXXPROC
- In the
Module field, type the location and name of the ODBC XA switch module created in the earlier steps, for example:
C:\Program Files (x86)\Micro Focus\Enterprise Developer\src\enterpriseserver\xa\ESODBCXA.dll
Note: When specifying the location and name of the ODBC XA switch module, do not enter an environment variable such as
%ProgramFiles(x86)%. Ensure that you use an expanded path.
- In the
Open string field, type
DSN=SAMPLE
Where
SAMPLE is the
Data source name specified in the
ODBC Data Source Administrator.
- You may need to add the ID and PASSWORD if connecting to a remote database. See
Generic one-phase commit for ODBC xa_open string for more information.
- Click
Add.
See
To define an XA resource (XAR) for an enterprise server region for more information.
Configure the program paths for data set catalog
You need to specify the JES program paths so that
COBOL Server automatically finds the application files that it needs to run:
- Click
.
- In the
JES Program Path field, leave the default value unchanged, $IDE_LOADLIB.
- In the
System Catalog field, type
C:\Users\Public\REXXSAMPLE\Test1\catalog.dat
- In the
Default Allocated Dataset Location field, type
C:\Users\Public\REXXSAMPLE\Test1
- In the
System Procedure Library field, leave the default value unchanged, SYS1.PROCLIB
- Click
Apply.
Start the
enterprise server region
- In Server Explorer, expand
Local [localhost:86].
- Right-click
REXX32, and then click
Start.
Note: The
Enterprise Server Sign On dialog box might prompt you to provide connection details for the server. This is a standard security dialog box. Click
OK without specifying any sign-on details. Also, if prompted to disable password recovery, click
No.
- If you receive a Windows Security Alert for the MF Communications Process, click
Allow access.
Catalog the directories that have the REXX procedures
You need to specify the catalog file that holds details of the data sets required by the JCL job that run in an
enterprise server region. To do this you need to create a Dynamic PDS. See
Dynamic PDSs for more information.
- In Server Explorer, right-click
REXX32 under
Local [localhost:86].
- Click
Show Catalog.
- Click
List.
- Click
New.
- In the
DS Name field, type
USER.TEST.EXEC
- In the
Physical File field, type
C:\Users\Public\REXXSAMPLE\Test1\Scripts
- From the
DS Org list, select
PO.
- From the
RECFM list, select
LSEQ.
- Check
Dynamic PDS.
- In the
PDS Exts field, type
rex
- Click
Apply.
To run the JCL job
- In
Application Explorer view, expand the project to show the
Test1.jcl file.
- Right-click the
Test1.jcl file, and then click
Submit JCL to associated Server.
View the spool output
You can check the result of submitting the JCL job by viewing the spool:
- In Server Explorer, expand
Local [localhost:86].
- Right-click
REXX32.
- Click
Show Spool.
- Click
REXXTEST.
This provides more information on the job submitted.
- Click
SYSTSPRT for either of the steps to see more information.
The following message or similar is displayed for STEP10:
DROPPING REXTEST1 TABLE
INSERTING DATA
PREPARING S1
FETCHING DATA
TEST PASSED -33329.3333
INSERTING DATA USING INSQLDA
PREPARING S3
FETCHING DATA USING OUTSQLDA
TEST PASSED -33329.3333