On Sun, May 13, 2012 at 02:11:15PM +0300, Timour Katchaounov wrote:

=== modified file 'sql/sys_vars.cc' --- a/sql/sys_vars.cc 2012-04-19 14:00:13 +0000 +++ b/sql/sys_vars.cc 2012-05-11 15:25:03 +0000 @@ -3780,4 +3780,9 @@ static Sys_var_ulong Sys_debug_binlog_fs CMD_LINE(REQUIRED_ARG), VALID_RANGE(0, UINT_MAX), DEFAULT(0), BLOCK_SIZE(1)); #endif - +static Sys_var_harows Sys_expensive_subquery_limit( + "expensive_subquery_limit", + "The maximum number of rows a subquery examines in order to be " + "considered non-expensive", + SESSION_VAR(expensive_subquery_limit), CMD_LINE(REQUIRED_ARG), + VALID_RANGE(0, HA_POS_ERROR), DEFAULT(100), BLOCK_SIZE(1));

"considered non-expensive" may not mean much for the outside user. Please change the wording to explicitly say that subqueries that enumerate less than expensive_subquery_limit rows may be evaluated at the optimization phase. Which version will this fix be pushed to? 5.5-ga? BR Sergei -- Sergei Petrunia, Software Developer Monty Program AB, http://askmonty.org Blog: http://s.petrunia.net/blog