Utility Statements › REORG › Usage › Initiating a REORG Operation

Initiating a REORG Operation

Specifying setup options

A reorganization is initiated when a REORG statement is executed that specifies setup-options. The setup-options describe the segment to reorganize and the processing options to use. The first phase of the reorganization is called setup. During this phase, the parameters and the structure of both the source and target databases are analyzed to determine the tasks to perform and the work files that are needed. The result of this analysis is then written to the reorganization control file (RORGCTL). All subsequent reorganization jobs read the control file to determine what to do and how to do it.

Important! Be sure that setup-options are specified only when you intend to initiate a new REORG operation. Their presence causes the RORGCTL file to be overwritten, which results in the failure of any in-progress REORG operation using that control file.

The source/target subschemas

The REORG utility uses information in the dictionary when processing an SQL-defined database. When processing a non-SQL-defined database, the description of the data is contained in the source and target subschemas.

The source subschema describes the data to be unloaded and must:

• Include the areas being unloaded
• Include all areas containing records with set connections to records in the areas being unloaded
• Define all record types in the areas being unloaded
• Define all sets in which the record types participate
• Define all record types that can participate in the defined sets

The target subschema describes the data to be reloaded and must:

• Define the same record names and sets as the source subschema
• Include the areas into which data is to be reloaded and all areas containing records with set connections to those areas
• Allow all included areas to be readied in exclusive update mode

The source subschema must be available during the setup and unload phases. The target subschema must be available during the setup, unload, and reload phases.

The source segment and the target database

The source segment, which is the segment named in the SEGMENT clause of the REORG statement, must include all areas being reorganized. If these areas are physically connected to other areas, either:

• These other areas must be part of the source segment, or
• These areas must be part of segments that are included in a DBNAME whose name is the same as that of the source segment

The target database, which is the database named in the INTO clause of the REORG statement, must include all areas into which data is to be reloaded as part of the REORG operation. If these areas are in different segments or are physically connected to areas in other segments, the target database must be a DBNAME that includes all of these segments.

Note: For more information about inter-area considerations, see Cross-area dependencies and Cross-segment dependencies in Special Database Considerations.

The source/target DMCLs

The source DMCL must include the source segment and all segments with which the source areas are physically linked. The target DMCL must include the target segments and all segments with which the target areas are physically linked. Both the source and target DMCLs must be available during the setup and unload phases of the REORG operation. The target DMCL must also be available during the reload and cleanup phases.

The source DMCL is the DMCL specified in the SYSIDMS file. If no DMCL is specified in the SYSIDMS file, the DMCL named IDMSDMCL is used.

The target DMCL is the DMCL named in the INTO clause of the REORG statement. If no DMCL is specified in the INTO clause, the source DMCL is used as the target. If the same DMCL is used as both source and target, then either this DMCL must include both the source and target segments or no segment-related changes can be made to the data being reorganized.