Oracle·ÖÎö±íºÍË÷Òý(analyze)
analyze table tablename compute statistics;
analyze index indexname compute statistics;
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Use the ANALYZE statement to collect non-optimizer statistics, for example, to:
1¡¢Collect or delete statistics about an index or index partition, table or table partition, index-organized table, cluster, or scalar object attribute.
2¡¢Validate the structure of an index or index partition, table or table partition, index-organized table, cluster, or object reference (REF).
3¡¢Identify migrated and chained rows of a table or cluster.
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