Method, system, and program for collecting statistics of data stored in a database

摘要

The present invention relates to collecting statistics automatically for data in a database. There is provided a method for automated statistics collection comprising determining a likelihood that statistics for data have changed; and collecting statistics for data in response to the likelihood. Indicators of the likelihood that statistics have changed may be useful to trigger automated statistics collection. Tables having statistics that change significantly may be collected more often than statistics of tables that are stable. A preferred model is provided to facilitate the collection of statistics that are more relevant: a table is scheduled for collection in accordance with observed patterns of table activity; a table is considered for collection if it meets a threshold level of activity; and a table is sampled to predict whether the statistics to be collected have changed. When collecting statistics, throttling and lock contention can minimize impact on a database user's response experience.