"If you are using this option with CHECK TABLE, it will ensure that the table is 100 percent consistent, but will take a long time. If you are using this option with REPAIR TABLE, it will run an extended repair on the table, which may not only take a long time to execute, but may produce a lot of garbage rows also!",
"If you are using this option with CHECK TABLE, it will ensure that the table is 100 percent consistent, but will take a long time. If you are using this option with REPAIR TABLE, it will force using old slow repair with keycache method, instead of much faster repair by sorting.",