Troubleshooting VSAM Data Files

CONNX CDD warning message appears: "Warning: Column #XXX has a offset+length greater than the record size." (where #XXX is the column number).

This warning message appears whenever there is a discrepancy between VSAM data file record length and the CONNX Data Dictionary table record length created for the data file. In the warning message box, the column number is displayed showing where the discrepancy begins.

IMPORTANT:
Any CONNX CDD table returning this warning will not yield correct results for any column beyond the column number specified in this warning message!

 

  1. Files with variable record length:

    A variable length record within a VSAM file can be longer than the record length value displayed on the Table Properties tab in the CONNX Data Dictionary Manager window. Repetitive record segments (also known as arrays) are found within VSAM file structures. Instead of a fixed number of repetitions, the number varies based on a counter field value stored within each record. Since the length of each record is calculated individually, the total record length can be different for each record in the VSAM file.

    Any VSAM data file containing repeating segments using counter fields should be imported into separate CDD tables to ensure offset accuracy.

  2. Files with fixed record length:

    The record imported or built in the CONNX Data Dictionary does not have the same record length as the actual VSAM data file.

    You can use the IBM IDCAMS utility to check the length of a VSAM file. A demonstration of how to list the VSAM file attributes is shown in the following graphics which list the VSAM file attributes from the OS/390 ISPF option 3.4 (Figures 1 through 7) and the VSAM file attributes achieved via an IDCAMS command invoked via the TSO shell (Figures 8 through 9):

List VSAM File Attributes from the OS/390 ISPF Option 3.4

Figure 1
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Figure 2
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Figure 3
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Figure 4
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Figure 5
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Figure 6
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Figure 7
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List VSAM File Attributes via a TSO Command
Figure 8
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Figure 9
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  1. VSAM file has a fixed record length and the two record lengths agree:

    You can verify that a VSAM file contains fixed length records by executing a LISTCAT command as in Step 2. The AVGLRECL and MAXLRECL values are equal for fixed-length VSAM files.