Hi guys, i'm checking a dump optimization, probably a problem: EXPLAIN SELECT * FROM table WHERE pk1=1001 AND pk2='v' AND pk3=19808671980883 pk3 = bigint, pk1=integer, pkg2=enum('v','i','c') this return "Impossible WHERE noticed after reading const tables", my max(pk3) = 1923425, pk1 and pk2 exists but: EXPLAIN UPDATE table SET field1=1234 WHERE pk1=1001 AND pk2='v' AND pk3=19808671980883 shows: index=PRIMARY - rows = 1.055.901 - Using where maybe update didn't check max value? it's a INNODB engine this execute a full table read, and slowquery # Query_time: 15.440127 Lock_time: 0.000079 Rows_sent: 0 Rows_examined: 1.914.183 (more than table rows) -- thanks