>>>>>what about text search engin if there any option.
>>>>
>>>>Did you check the thread I pointed you to? The other option may be to switch to SQL Server.
>>>
>>>Do you think SQL-Server will do it quicker?
>>
>>Yes, with Full Text Search.
>>http://www.developer.com/db/article.php/3446891
>
>I'm sure that 'all words' table could make it faster than anything.
>Btw, I made some testing with a table of similar (as told in the thread) size. First query was slow enough (6 sec), but all subsequent were almost instant (big surprise :). So one could just fool users by running something on background.

Did you use the same word in next queries?