RDF System Management Manual

Maintaining the Databases
HP NonStop RDF System Management Manual—524388-003
6-6
NonStop SQL/MP or NonStop SQL/MX Databases
It is safe to perform these operations just like other DDL operations on the primary
system.
DDL Operation Example
This example shows the SQLCI/MXCI commands for adding an index to a table and
the order of the operations:
1. Specify the default catalog for the backup system.
CATALOG \BACK.$TEST.DBCAT;
2. Create an index on the backup system.
CREATE INDEX \BACK.$DATA1.DB.FIRST
ON \BACK.$DATA1.DB.EMPLOYEE( FIRST_NAME, LAST_NAME );
3. Specify the default catalog for the primary system.
CATALOG \PRIM.$TEST.DBCAT;
4. Create an index on the primary system that corresponds to the index created on
the backup system.
CREATE INDEX \PRIM.$DATA1.DB.FIRST
ON \PRIM.$DATA1.DB.EMPLOYEE( FIRST_NAME, LAST_NAME );
Note that you should use WITH SHARED ACCESS for the CREATE INDEX operations
in the above example if both RDF and the application are running.
Multiple Indexes On a Single Base Table
Note that these same issues also apply to NonStop SQL/MX.
If there are multiple indexes on a single base table, special considerations apply when
you use SQLCI CREATE INDEX commands on the backup system to coordinate
NonStop SQL/MP DDL operations between the primary and backup databases.
Each NonStop SQL/MP index is assigned a unique key specifier that is stored as part
of the key for that index. You can explicitly define the key specifier by including the
KEYTAG clause in the CREATE INDEX command. If you do not do so, then the
CREATE INDEX operation assigns a numeric value based on the order of index
creation (1, 2, 3, and so forth).
Because the key specifier is part of the key of every index row created on an RDF
primary system, it also becomes part of the associated TMF audit record. RDF
transmits the audit record to the backup system where it is then applied to the backup
copy of the index.
If a CREATE INDEX command on the backup system does not include the KEYTAG
clause (and if you are not extremely careful to create the indexes in the order shown by
a SQLCI FILEINFO <base table>, DETAIL command on the primary system), it is
possible for the key specifier of a backup index to be different than that of the primary
index. In such a case, the index rows transmitted from the primary system to the