Hi there, I hope someone will can help me... First, sorry for bad english :) i'm french First all I have those index in my table +-------+-------------------+-----------------+--------------------+-------- --------------+-------------+----------------+--------------+------------+-- ------------+ | Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Comment | +-------+-------------------+-----------------+--------------------+-------- --------------+-------------+----------------+--------------+------------+-- ------------+ | Stats | 0 | PRIMARY | 1 | ID | A | 4568748 | NULL | NULL | | | Stats | 1 | Port_ID | 1 | Port_ID | A | 1 | NULL | NULL | | | Stats | 1 | Timestamp | 1 | Timestamp | A | 49126 | NULL | NULL | | +-------+-------------------+-----------------+--------------------+-------- --------------+-------------+----------------+--------------+------------+-- ------------+
You have to know I have 4 500 000 in my db Okay I have this query: select Timestamp from Stats use index (Timestamp) where Timestamp >= '2002-01-01' and Timestamp < '2002-02-01' order by Timestamp limit 1; this one is jsut doing fine.. it take 0.00 sec to do it... but select Timestamp from Stats use index (Timestamp) where Timestamp >= '2002-01-01' and Timestamp < '2002-02-01' order by Timestamp desc limit 1; this one take sometime 10 sec to do.... I understand is the desc the prob.. because my index is in asc (collation=A) my question is... is there a way for maiking a index in desc? or maybe something else? Jean-Francois Dionne Yard --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
