The SQL statement "OPTIMIZE TABLE table " lets you specify a table (or several tables, with commas in between) that you would like MySQL to optimise. Notice the spelling is with a Z in the statement. By "optimise", I mean tables that have had a lot of changes made to them since they were created - lots of rows added/deleted/edited, etc; especially if the table uses varying length fields like VARCHARs and TEXTs. OPTIMIZE TABLE instructs MySQL to basically defragment the table to make it faster to read and write from.
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