A number of ODBC demonstration applications are supplied in the Samples Browser, available from Start > All Programs > Micro Focus Visual COBOL > Samples . These files are located in the %PUBLIC%\Documents\Micro Focus\Visual COBOL\Samples\sql\openesql (Windows) or $COBDIR/demo/sql/openesql (UNIX) directory by default.
Each sample application comes with a README.txt file to explain how to use the application, and a makefile. (applies to UNIX environments only)
Before you can use any of the demonstration applications, you need to have installed at least one ODBC driver, and created DSNs to use with the demonstrations.
Some of the demonstration applications expect that a table called EMP exists on the database to which you are connecting.
The OpenESQL demonstration applications all produce a console log displaying their progress and, possibly, query results. They all terminate on receipt of an error, after displaying an error message.
The following applications are provided:
Connects to a data source name LocalServer using the Microsoft SQL Server ODBC driver. To do this, see the Help topic To set up an ODBC data source name.
The program creates and populates a table used by behavior.cbl and behavsub.cbl. After the table is created, we show how the BEHAVIOR directive makes the same ambiguous COBOL cursor declaration read only in behavior.cbl and updateable in behavsub.cbl.
You can verify this by looking at the trace file OpenESQLTrace.processID.log, in the project directory. The log file is generated by the TRACELEVEL directive in behavior.cbl.
Displays an SQL Data Sources dialog. Enter or select a name and click on OK. A Login dialog is displayed. Enter a login name of "admin", leave the password blank and click on OK. Performs three data dictionary queries and outputs the results.
Prompts for a data source, user name and password. Enter the data source name you created, a user name of "admin" and leave the password blank (just press return). Four tests which perform connects and disconnects using a variety of syntax options are run. The fifth test displays an SQL Data Sources dialog. Select the appropriate name from the Machine Data Source list and click on OK. A Login dialog is displayed. Enter a login name of "admin", leave the password blank and click on OK. The fifth test is run and the program terminates.
Connects to the sample database and prompts for a customer code. Enter BLUEL (as the prompt suggests). Two fields from the customer record are displayed and the program prompts for another customer code. Just press the return key this time. The program prompts for a region. Enter CA (as the prompt suggests). The program displays a list of customers in that region and prompts for another region. This time, press the return key to terminate the program.
Both applications run the same sequence of tests, but using different SQL syntax options. They both start by prompting for a data source and user name. The test sequence is:
Step two may output an error message - this is expected and the programs will continue. The final stage should produce an error message, and again this is not treated as a genuine error (though the absence of an ODBC error is treated as a test failure).
Attempts to connect and displays an error message. Displays an SQL Data Sources dialog. Select the DSN name you created and click on OK. A Login dialog is displayed. Enter a login name of "admin", leave the password blank and click on OK. Tests error handling and outputs two error messages.
The file testconn.cbl is an OpenESQL demonstration program that shows how to use different formats of the CONNECT and DISCONNECT statements.
The file catalog.cbl is an OpenESQL demonstration program that shows how to use the ODBC catalog functions from COBOL.
The file static.cbl is an OpenESQL demonstration program that shows how to use basic SQL functions from COBOL. It demonstrates the use of INSERT, UPDATE, DELETE, SELECT INTO and SELECT using a cursor. It also shows the use of COMMIT and ROLLBACK.
The file dynquery.cbl is an OpenESQL demonstration program that shows how to use dynamic SQL functions from COBOL. It provides the capability for the user to enter any SQL statement and the program will execute them. It shows how to prepare a SQL statement and how to use the SQLDA structure to retrieve data from columns when the type of the column is not known when the program is compiled.
If you are accessing the EMP table described above, a sample query would be:
select FIRST_NAME, LAST_NAME, HIRE_DATE, SALARY from EMP