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

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 eBusiness 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.