IBM Books

Statistics for the table

Select one of the following radio buttons to specify whether and how you want the table's statistics updated:

Do not update
Statistics for the table are not updated. This is the default.

Update without distribution statistics
Basic-level statistics on the table data are updated in the system catalog tables. An example of a basic-level statistic is the number of pages being used by the table.

Distribution statistics on values in table columns are not collected.

Update with distribution statistics
Basic-level statistics on the table data are updated in the system catalog tables, and statistics of the distribution of data values in the table columns are collected. The query optimizer uses these statistics to more accurately estimate the number of rows in a column that satisfy given equalities or ranges.

An example of a distribution statistic is the frequency with which a particular data value occurs in a column.

Note:You cannot gather statistics during the load process if you selected Insert or Restart for the Load mode field on the Counts page of the Load notebook.

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