Business Intelligence Tutorial

Collecting table statistics

Table statistics provide information about the physical and logical characteristics of a table and its indexes. You must periodically collect these statistics, so that DB2 Universal Database can determine the best way to access your data. If extensive changes are made to the data in a table, and the last collection of statistics no longer reflects the actual table data, then data access performance can deteriorate. In general, you should update statistics if there are major changes to the data in your table.

To collect statistics on the LOOKUP_MARKET table:

  1. From the DB2 Control Center, right-click on the LOOKUP_MARKET table and click Run Statistics.

    The Run Statistics window opens.

  2. Use the online help to determine the level of statistics that you want to gather for the table and its indexes.
  3. Use Share level to specify the type of access that users have while statistics are being gathered.

    Change (Table read/write allowed)
    Other users can read and write to the table.

    Reference (Table read only)
    Other users have read-only access to the table.

    The GEOGRAPHIES SELECT statement on the SQL Statement page.
  4. Click OK to begin collecting the table statistics.


[ Top of Page | Previous Page | Next Page | Table of Contents ]