FW: Different flavors of relational database

Discussion created by ca.portal.admin on May 2, 2006
Latest reply on May 2, 2006 by ca.portal.admin
One reason you may see this is that a relational database does a table
scan only across the pages that contain the table rows (it keeps track
of this stuff).
IDMS does not know that instances of record X are only on pages 4, 12,
28, and 56. It must examine every page of the area looking for
instances. So if you put record X in the same area as records A, B, and
C and the area is 10,000 pages, then IDMS reads 10,000 pages while SQL
reads 4 pages (4, 12, 28, and 56).

If you were to put each record in its own private area (or sub-area)
with just enough pages to hold the number of records you area loading,
then you would see comparable timings.

Richard S. Kenney