Perform SQL select with JCL(SELTBL)

[vargajb]

Signed-off-by: Janos Varga 113785741+vargajb@users.noreply.github.com

Proposed changes

I document that by running JCL(SELTBL) it is possible to check whether the data has been loaded in the Db2 table. The JCL(SELTBL) job has been available for more than a year, but it was not included in the documentation.

Fixes # (issue)

Type of change

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• Bug fix (change which fixes one or more issues)
• New feature (change which adds functionality or features to the course)
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[vargajb]

@tanto259 I read through the COBOL programming course and found some things to improve. I am now submitting these improvements one by one in small steps. I use small steps because I think it's easier to handle that way. In the next few days, I would pull a few more requests. :)

[tanto259]

This is a nice addition. Thanks, @vargajb!