Overview of the Index Build function

• All secondary indexes of a database
• Selected secondary indexes
• The primary index of a HIDAM or PHIDAM database
• The ILDS of a PHDAM or PHIDAM database

Using the PRIMIND keyword, you can build the primary and secondary indexes in one step (and one scan of the database).

The Index Build function makes it easy to create and maintain JCL. You can use existing SECONDARY INDEX UTILITY or MAXM Reorg classic JCL. The Index Build function automatically converts most SECONDARY INDEX UTILITY and MAXM Reorg classic keywords to the Index Build function format.

When you implement a new secondary index for a primary database, add to the JCL a DD statement that defines the new secondary index.

The Index Build function can scan the primary database, or it can use the input data set that you specify with the INDD keyword. BMC recommends that you use the INDD(DFSURWF1) keyword if the Index Build function is being executed during a complete database reorganization. Using an INDD keyword can eliminate redundant processing to recreate index records that might already exist in a DFSURWF1 file. If you do not specify an INDD keyword, the Index Build function scans the primary database to create the index records.

The Index Build function works as follows:

1. During initialization, the Index Build function obtains information about the secondary indexes from the DBD of the primary (target) database.
2. If no INDD keyword is specified, the Index Build function scans the primary database and creates the index records. The Index Build function selects the scan method (hierarchical or sequential) that is most efficient for the database. If the job specifies a SCAN keyword (supported in earlier releases), processing continues but the SCAN keyword is ignored.
3. The Index Build function invokes your installation’s sort product to sort the index records by index and VSAM key field.
4. The Index Build function loads the selected indexes.

The following figure shows the system flow for the Index Build function.

The Index Build function accepts output from the following utilities:

• Reload function
• IMS HD Reorganization Reload

The Index Build function provides an automated interface to DBRC. For more information, see DBRC-support