SQL/MP Version Management Guide

Compaq NonStop™ SQL/MP Version Management Guide—429833-001
3-1
3
Database Versions
To specify the version of a NonStopSQL/MP user catalog or system catalog, you use
two different types of version numbers:
•
Catalog version
Every user catalog and every system catalog has a catalog version number. A
catalog version number identifies the newest version of SQL objects that can be
registered in a user or system catalog. The number is determined by the version of
the SQL/MP software used to create the catalog.
•
Catalog format version
Every user catalog and system catalog also has a catalog format version number. A
catalog format version number identifies the physical structure of the catalog and
also specifies the oldest version of SQL/MP software that can access the catalog.
SQL/MP Catalog Versions
When a new version of SQL/MP software is released because of the introduction of one
or more new features, a new catalog version number is also assigned, although the new
feature(s) might not affect the physical structure or the contents of the catalog.
A different version number, the catalog format version, reflects the physical structure of
a catalog. The catalog format version of a catalog, unlike the catalog version, changes
only when the structure of the catalog changes. The catalog format version number is
described in the Catalog Format Version
on page 3-2.
When a catalog is assigned a new catalog format version number, it is also assigned a
new catalog version number. Because the catalog format version number does not
always change when its corresponding catalog version number changes, a catalog format
version number is always equal to or less than its corresponding catalog version number.
Because the catalog version number of a catalog changes both every time a new version
of SQL/MP is released and when the physical structure of the catalog changes, a catalog
version number can be higher than the version numbers of the objects registered in the
catalog, but it cannot be lower. For example, a version 310 catalog can register version
1, version 2, or version 300 objects, in addition to version 310 objects, but it cannot
register objects with version numbers greater than 310.
Similarly, a version 2 catalog can register either version 1 or version 2 objects, but not
version 300 or newer objects. A version 1 catalog can register only version 1 objects.
These relationships are illustrated in Figure 3-1
.