Post-installation actions on data store VSAM files

About this task

While primary and secondary indexes need to be initialized, data files are initialized automatically at data store startup. To add a new data file, create it and add it to the data store startup procedure. However, after a data file has been initialized, it cannot be removed from the procedure. To reallocate a data file, the primary and secondary indexes must be reallocated too.

When VSAM local and remote data files fill up:
  1. Make a copy of all the data files and primary and secondary indexes to temporary files by using the REPRO function of IDCAMS.
  2. DELETE and DEFINE clusters, to increase the allocated space.
  3. Use the REPRO function to copy the temporary files into the new allocated VSAM files.
  4. If needed, define new data files and add them to the data store procedure. The data files will be initialized the first time data store starts up.

Instead of IDCAMS, you can also use the EXPORT and IMPORT utilities. This method is slower but reorganizes the data files as well. Reorganizing the data files means that all the lost space is recovered, although this has no impact on data store performances.

To reduce the number of data files, use the EXPORT and IMPORT utilities. After the EXPORT phase, you can DELETE and DEFINE clusters and reduce their number.

When a primary or secondary index is corrupted, use the RECOVER utility that, starting from data files, reconstructs them. The recovery of both the primary and secondary indexes starts from the same utility, which reads data files to recover the primary index first.