SQL_CALC_FOUND_ROWS or two queries
While reading few posts I found that SQL_CALC_FOUND_ROWS is faster than two queries. But a very good discussion found at http://www.mysqlperformanceblog.com/2007/08/28/to-sql_calc_found_rows-or-not-to-sql_calc_found_rows/comment-page-1/#comment-661064. check this out
One member posted following on above blog which is worth to read
Please visit the mysql official documentation here http://dev.mysql.com/doc/refman/5.1/en/information-functions.html
Please have a look at FOUND_ROWS() function. They have mentioned that it is much faster to use the query with sql_calc_found_rows rather than using a query again. And I don’t find any reason not to trust them.