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MySQL Syntax: ANALYZE TABLE table_name
http://dev.mysql.com/doc/refman/5.5/en/analyze-table.html
PostgreSQL Syntax: ANALYZE table_name
http://www.postgresql.org/docs/8.4/static/sql-analyze.html
Oracle Syntax: exec dbms_stats.gather_table_stats('schema', 'table_name', cascade => TRUE);
Or this: EXEC DBMS_STATS.gather_schema_stats('schema');
http://download.oracle.com/docs/cd/B19306_01/appdev.102/b14258/d_stats.htm
Note, you can analyze a subset of the rows in oracle if you have a lot of data
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