Hi!

On Dec 04, tk wrote:
> Hello,
> 
> Thanks for the response. 
> There is one thing that is not clear however. 
> 
> Regardless of whether or not I perform the fulltext
> search with or without the SQL_CALC_FOUND_ROWS
> keyword, the results that I get are exactly the same. 
> 
> Also, the notion of stopping after the limit is
> reached cannot apply in the fulltext search or
> otherwise we would only get the first 10 matches but
> not the first 10 "most relevant" matches. This leads
> me to believe that the fulltext search must be looking
> at all the rows in both cases since it otherwise would
> not find the same first 10 most relevant records.
> Hence the question why there should be a difference in
> time.

The difference is that you only need to read 10 rows from the disk
without SQL_CALC_FOUND_ROWS.

With SQL_CALC_FOUND_ROWS MySQL goes on and reads all rows, it takes
time.

Finding relevant rows and sorting is based on index only, row data are
not read.
 
Regards,
Sergei

-- 
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  /  |/  /_ __/ __/ __ \/ /   Sergei Golubchik <[EMAIL PROTECTED]>
 / /|_/ / // /\ \/ /_/ / /__  MySQL AB, Senior Software Developer
/_/  /_/\_, /___/\___\_\___/  Osnabrueck, Germany
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