The target page for a CALC record is determined by the IDMSCALC routine. A CALC record is stored on the target page unless that page is full. If the target page is full and the TARGETROOT parameter was not specified, CA IDMS/DB Reorg finds the next available page in the record's page range that can accommodate the entire record.
If CALC records must overflow to another page, CA IDMS/DB Reorg overflows the CALC records with symbolic keys that are higher than those of records stored on the home page. This reduces the average number of I/Os required to retrieve CALC records.
When a variable length CALC record does not fit on the target page, but the target page can accommodate the root portion and TARGETROOT parameter was specified, CA IDMS/DB Reorg stores the record in two parts. The root is stored on the target page and the rest of the record (the record fragment) is stored on the first available page which can fit the entire fragment.
In the database, duplicate CALC keys maintain the same order as in the old database.
Optimizing the CALC Set:
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