Usage and restrictions

There are important usage and restrictions for the IMS HALDB Toolkit product.

Logical relationships and secondary indexes

IMS HALDB Toolkit converts databases and secondary indexes with the following logical relationships:
  • Unidirectional logical relationships remain as unidirectional.
  • Bidirectional logical relationships with physical pairing remain as bidirectional with physical pairing.
  • Bidirectional logical relationships with virtual pairing are converted to bidirectional relationships with physical pairing.
  • Shared secondary indexes are converted to single secondary indexes.
  • Non-unique secondary indexes are converted to unique secondary indexes by adding the /SX field to the SUBSEQ parameters of the XDFLD.

A few installations have defined bidirectional logical relationships without any pairing even though this capability is not documented in the IMS product. IMS HALDB Toolkit does not support a conversion of these relationships to HALDB.

When running the CONVERT function as a batch job, DBDs with logical relationships (except for indexes) are not allowed. To convert DBDs with logical relationships, the ISPF interface must be used because the database and all logically related databases must be unloaded before the conversion can be done. Batch CONVERT does only one unload followed by one convert at a time. The ISPF interface can be used to construct the JCL such that all unloads are to be done before the conversion.

The CONVERT function does work for DBDs with logically related secondary indexes. The CONVERT function always converts the related non-HALDB Secondary Index to a HALDB Secondary Index (PSINDEX for example). This conversion from non-HALDB Secondary Index to a HALDB Secondary Index is so that the secondary index remains usable. If the secondary index is no longer required, one must remove it from the DBD and run DBDGEN again before running the CONVERT function.

Database limitations

The following limitations apply to IMS HALDB Toolkit database conversions:

  • SHISAM, HSAM, and DEDB databases cannot be converted.
  • HISAM databases are converted to PHIDAM.

The MAINTAIN function does not support HALDB M-V data sets.

The MAINTAIN function processes PSINDEXes only when the PSINDEXes are offline.

Restrictions for OSAM LDSs

  • The CONVERT and MAINTAIN functions do not support image copy of VSAM linear data sets (OSAM LDSs) to DASD when the CI size of the data sets is 32K.
  • The MAINTAIN function does not support the mixed use of OSAM sequential data sets and VSAM linear data sets (OSAM LDSs) as input DBDS.