STATISTICS

Default: ESTIMATE

Specifies the type of database optimizer statistics to generate when the exported data is imported. Options are ESTIMATE, COMPUTE, and NONE.

In some cases, Export will place the precalculated statistics in the export file, and also the ANALYZE statements to regenerate the statistics.

However, the precalculated optimizer statistics will not be used at export time if a table has columns with system-generated names.

The precalculated optimizer statistics are flagged as questionable at export time if:

• There are row errors while exporting

• The client character set or NCHAR character set does not match the server character set or NCHAR character set

• A QUERY clause is specified

• Only certain partitions or subpartitions are exported

  Note:

  Specifying ROWS=n does not preclude saving the precalculated statistics in the export file. This enables you to tune plan generation for queries in a nonproduction database using statistics from a production database.