Default language.

Data Packer supported database types and organizations


BMC AMI Data Packer for IMS

 supports several types of databases and database organizations.

The following table summarizes the database organizations and access methods that Data Packer supports.

IMS databases and access methods that Data Packer supports

Database organization

Access method

Full-function

  • Hierarchic indexed sequential access method (HISAM)
  • Hierarchic direct access method (HDAM)
  • Hierarchic indexed direct access method (HIDAM)

VSAM or OSAM

High-availability large data bases (HALDBs)

  • Partitioned hierarchic direct access method (PHDAM)
  • Partitioned hierarchic indexed direct access method (PHIDAM)

VSAM or OSAM

Fast Path

  • Data entry database (DEDB)

VSAM

Consider the following points regarding database compression:

  • Typically, HISAM database segments are not good candidates for compression. If you compress a HISAM database record that completely fits in the same logical record, actual DASD savings are minimal: the compression percentage achieved does not reduce the number of logical records that are stored on DASD. The only effect of compressing these records is that each logical record on DASD contains additional wasted free space.
  • If HISAM database records tend to span more than one logical record and use overflow, compression can reduce the amount of DASD that is required by reducing the amount of overflow space being used. Never compress a HISAM root-only database because no DASD savings can be achieved.
  • Because IMS does not allow you to code a compression exit in a simple hierarchic indexed sequential access method (SHISAM) or hierarchic sequential access method (HSAM) DBD, Data Packer cannot compress SHISAM or HSAM databases.

 

Tip: For faster searching, add an asterisk to the end of your partial query. Example: cert*