Functions of FPA

Unload

The Unload function of FPA efficiently unloads a single DEDB area. It can also concurrently unload multiple DEDB areas without impacting all areas of a database. Specifically, the Unload function unloads multiple DEDB areas to QSAM data sets. If necessary, a sort step can be included in the Unload process. Optionally an image copy can be generated after completing the Unload process.

Reload

The Reload function of FPA efficiently reloads a single DEDB area. It can also concurrently reload multiple DEDB areas without impacting all areas of a database. Specifically, the Reload function reloads multiple DEDB areas from the QSAM data sets. If necessary, a sort step and an analyze step can be included in the Reload process. Optionally an image copy can be generated after completing the Reload process.

Change

The Change function of FPA efficiently reorganizes or restructures a single DEDB area. It can also concurrently reorganize or restructure multiple DEDB areas without impacting all areas of a database. Specifically, the Change function reorganizes or restructures multiple DEDB areas in one step. If necessary, an analyze step can be included in the Change process. Optionally an image copy can be generated after completing the Change process.

Reorg

The Reorg function reorganizes a set of UOWs in a DEDB area on the basis of a ranked set of UOWs. The Reorg function includes the UOW Evaluation phase where the reorganization free space score (RFS score) for a set of UOWs of the DEDB area is determined. In the UOW Ranking phase that follows the UOW Evaluation phase, the Reorg function ranks the set of UOWs according to the RFS score. Finally, the highly ranked UOWs are reorganized up to the user-specified number of UOWs.

The Reorg function reduces the possibility of having too many or too few UOWs reorganized by ranking the set of UOWs in the DEDB area, and allows the user to select how the subset of the ranked set of UOWs is chosen. Consequently, the user can limit the size of the subset of UOWs that will be reorganized before the reorganization is done.

Analyze

The Analyze function provides a fast, efficient mechanism for verifying the integrity of all IMS pointer values, free space element chains, VSAM control fields, and space utilization in IMS DEDBs. It also provides simple integrity verification of pointer segments in secondary index databases. The Analyze function provides the comprehensive analysis information required to effectively manage the space utilization, performance characteristics, and physical attributes of IMS DEDBs. The Analyze function uses a VSAM ESDS or an image copy as input. The Analyze function can be an aid for database administrators and technical support personnel in database management and maintenance. Optionally an image copy can be generated after completing the Analyze process.

Tune

The Tune function provides a fast and efficient mechanism for tuning databases. The function simulates changes in the DBD parameters, randomizers, and segment edit/compression routines without loading the segments letting you select the physical database attributes that satisfy the performance and space utilization requirements.

The Tune function provides a comprehensive tuning facility for managing databases and optimal performance.

Extract

The Extract function provides an easy-to-use, flexible method to extract segment data from one or more offline DEDB areas and writes the output to QSAM data sets.

The Extract function can be used as an alternative to writing your own application to extract DEDB data. Other potential uses of this function include:

• Record reporting
• Extraction of records to populate a test database

DMAC Print

The DMAC Print function provides maps of the contents of the DMAC blocks for one or more areas by using the IMS mapping macro and the DMAC dump. DMAC is an important CI that has the information for ROOT, UOW definition, and SDEP LB/LE values, and so on, for a DEDB area data set. The DMAC Print function maps the global section and the local section with offset, label, and values. It also provides the dump that is specified by the DMAC length, EQE list, CUSN, and RBA.

Build Index

The Build Index function builds the secondary index databases from multiple DEDB areas.

Resync

The Resync function synchronizes a DEDB and its secondary index databases when they are out of synchronization. This function runs against online areas.

Freespace Reclaim

The Freespace Reclaim function reclaims the control intervals (CIs) in secondary index database data sets.

Initialize

The Initialize function of FPA efficiently initializes a single DEDB area. It can also concurrently initialize multiple DEDB areas.