Converting HDAM or HIDAM databases with secondary indexes to HALDB

Partitioned secondary indexes (PSINDEXes) are the only type of secondary index that HALDB databases support. When you convert HDAM or HIDAM databases that have secondary indexes to HALDB PHDAM or PHIDAM databases, you must also convert the secondary index databases to HALDB PSINDEX databases.

Create image copies of your database data sets and back up your RECON data sets and your existing DBD definitions.

To convert a target HDAM or HIDAM database and its secondary index to HALDB, the steps are essentially the same as those documented in greater detail in Converting simple HDAM or HIDAM databases to HALDB PHDAM or PHIDAM, except for the changes that are related to converting the secondary index and populating the ILDS.

You must define partition boundaries for the PSINDEX database. You can run the HALDB Migration Aid utility (DFSMAID0) against your existing secondary index to help you determine a partitioning scheme for your PSINDEX.

If you are using only the IMS base utilities for the conversion process, you can take either of the two following approaches when you convert your database and its secondary indexes:

  • To create secondary index output files as the HD Reorganization Unload utility (DFSURGU0) unloads the target database, specify the MIGRATX=YES control statement when you run the HD Reorganization Unload utility. The MIGRATX=YES control statement instructs the utility to create secondary index output files from the target segments of the indexed database without reading the secondary indexes. The MIGRATX=YES control statement method does not preserve any user data in the secondary indexes.
  • To convert the secondary index as a standalone database, specify the MIGRATE=YES control statement when you run the HD Reorganization Unload utility for both the indexed database and the each secondary index. This method requires that the HD Reorganization Unload utility read and unload each secondary index separately. When reading the secondary index, the utility must also read the indexed database.

    This information does not describe the MIGRATE=YES control statement method for converting secondary indexes to HALDB.

Recommendation: Use the MIGRATX=YES method.