Siebel Installation Guide for Microsoft Windows: Servers, Mobile Web Clients, Tools > Configuring the RDBMS > Configuring MS SQL Server for Siebel Applications >

Guidelines for Ongoing MS SQL Server Administration

After you have installed your Siebel application on Microsoft SQL Server, some other tasks must be performed on a periodic basis. These are in addition to such common database administration tasks as monitoring and backing up.

Updating MS SQL Server Statistics

The cost-based optimizer in Microsoft SQL Server uses statistics about tables and indexes to compute the most efficient access plans. When statistics become inaccurate, as can happen for tables with high insertion or deletion rates and for their associated indexes, the performance of database operations can degrade dramatically.

Perform a full scan of all tables under the following circumstances, even if you implement automatic statistics updating:

• After installing the Siebel Database and before starting Siebel Business Applications.
• After running concurrent EIM threads.
• After inserting, updating, or deleting large amounts of data.

Using Query Analyzer, perform a full scan of each table by entering the following command:

update statistics Table Name with full scan

It is strongly recommended that you enable the automatic creation and updating of statistics, using the parameters documented in Configuring MS SQL Server for Siebel Applications. This way, statistics are automatically kept up to date and the administrative overhead of updating them manually is removed.

If you do not implement automatic statistics updating, then periodically perform the full scan described in this section.

Managing MS SQL Server Fragmentation

Use the following Microsoft SQL Server command to determine whether a clustered index and its associated tables are highly fragmented:

DBCC SHOWCONTIG

If this command returns a value for scan density of less than 60%, use the following Microsoft SQL Server command to defragment tables without having to drop indexes:

DBCC INDEXDEFRAG

You may want to use this option periodically against the entire database.

If DBCC SHOWCONTIG returns a value of less than 30%, or when you suspect that indexes might be interleaved on the disk, consider rebuilding the index, using:

DBCC DBREINDEX

For more information about monitoring fragmentation, see the appropriate Microsoft SQL Server documentation.