Yes. Why? Because the alternate key would first locate the primary key, which in turn locates the actual record. Needs twice the number of I/Os.
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255 – but you must be a nut to have so many ALT Indexes on a dataset!
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only on KSDS and ESDS – not RRDS
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Out of space condition is raised.
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Define new VSAM dataset allocated with more space.
Use IDCAMS to REPRO the old VSAM file to new VSAM dataset.
Use IDCAMS to ALTER / rename the old VSAM dataset or se IDCAMS to DELETE the old VSAM dataset.
Use IDCAMS to ALTER / rename the new VSAM dataset to the name of the original VSAM dataset.
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Run VERIFY.
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Use the LISTCAT command.
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Give (+1) as the generation number, give (new,catlg) for disp, give space parameter, can give the DCB parameter if you want to override the dcb of the model dataset.
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Relative generation numbers are updated only at the end of the job, not at the end of a step. To allocate a new generation, we would be using (+1) with a DISP of (NEW,CATLG,DELETE). To refer to this in a subsequent step in the same job, we would again use (+1) but with a DISP of SHR or OLD.
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Use GDG name(-2).
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