If you change the update to a select you can use explain to see it's execution path just like you would with a normal select. The rows returned are the rows that would be matched by the update query. Example:
explain select * from t1, t2 where t1.YYY=t2.ZZZZ and t2.AAAA like '%X%'; Optimize the query then turn it back into an update. -Eric On Wed, 1 Dec 2004 11:38:29 +0530, Manish <[EMAIL PROTECTED]> wrote: > I am trying to execute this query and it is failing with Table is full error > (I know I can make temp tables big). > update t1, t2 > set t1.XXX=1 > where t1.YYY=t2.ZZZZ and t2.AAAA like '%X%'; > > My t1 has 10,00,000+ records and t2 has about 70,000 recorsds. I would like > to know how can I optimize this query? > What are the parmeters for this optimization? Can someone give me links > where I can read up about such optimizations for update query. > > TIA, > - Manish > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] > > -- Eric Bergen [EMAIL PROTECTED] bleated.com -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
