This document explains the purpose of segment SYSCAT.
Release : All supported releases
Component : CA IDMS/DB
SYSCAT is a SEGMENT which is defined in install library member TABLEDDL and as such is created when TABLEDDL is run against a catalog.
When a normal user-defined table is created, it is assigned a physical area for the data of that table to reside in.
The tables in the SYSTEM sql schema are always in an area with the name DDLCAT, but this area will be in a segment according to the database name connected to at run time.
Therefore, a dummy "place-holder" segment called SYSCAT is defined to represent that segment in the SYSTEM table definitions.
SYSCAT is never included in a DMCL and so the file names and page ranges in SYSCAT are meaningless.
At runtime, if an area being processed is one of the catalog area names, the segment name of SYSCAT is automatically replaced by the true physical segment name found in the currently connected DBNAME.
When running TABLEDDL, the source library member must not be editted and should be added as is.