SQL/MX 2.x Installation and Management Guide (H06.10+, J06.03+)

Adding, Altering, and Dropping SQL/MX Database
Objects
HP NonStop SQL/MX Installation and Management Guide—544536-007
9-12
Adding Partitions to SQL/MX Tables and Indexes
of the objects involved, parallel processing operates best when a table or index is
partitioned.
Use the Measure product to obtain statistics concerning disk message levels, queuing,
and other measurements on various volumes or file partitions to identify the levels of
use.
For more information about the benefits of new partitions, see Performance Benefits of
Partitioning on page 7-17.
Steps for Adding a Partition
1. Start an MXCI session. Enter a LOG command to initiate a log file for statements
and commands entered in this session. Keep the log for your records.
2. Determine the name of the table or index to which you want to add the partition.
3. For range partitioned tables or indexes, determine the location and starting key of
the new partition. For hash partitioned tables or indexes, determine the location of
the new partition.
4. Ensure ample disk space is available for the new partition. For information about
space requirements, see the SQL/MX Reference Manual.
5. Use the DISPLAY USE OF command to identify which user modules are
associated with this object. See the similarity check criteria in the SQL/MX
Programming Manual for C and COBOL to determine if your changes are likely to
cause similarly check to fail and force automatic recompilation. If they will, you
should SQL compile these modules after making the changes to avoid expensive
automatic recompilations at run time. SQL applications that are running while you
make these changes will still undergo automatic recompilation.
For information about explicit and automatic recompilation, see the SQL/MX
Programming Manual for C and COBOL. For information about using DISPLAY
USE OF, see Checking Module Dependencies with DISPLAY USE OF on
page 11-19 and the SQL/MX Reference Manual.
6. Use the MODIFY utility to add the partition. (See Using MODIFY to Manage Table
and Index Partitions on page 10-10.)
7. Revise the application source code as needed to reflect your changes to the
database. Process and compile the updated source file. For more information, see
the SQL/MX Programming Manual for C and COBOL.
8. Make new TMF online dumps of all partitions of the table or index.
For information about redistributing rows across partitions, see Section 10,
Reorganizing SQL/MX Tables and Maintaining Data.