DELETE LOW_PRIORITY
But since your using myISAM the table will have to lock. DVP ---- Dathan Vance Pattishall http://www.friendster.com > -----Original Message----- > From: Matthew Simpson [mailto:[EMAIL PROTECTED] > Sent: Friday, May 20, 2005 11:22 AM > To: mysql@lists.mysql.com > Subject: slow DELETE query > > I use Mysql to store call detail records from telephone > calls. I have around 20 voice switches that send the call > detail records in real time using INSERT statements. > > I am having a problem where I need to delete "junk" call > records that get generated [old call records, call records > with no accountcode, etc.], but when I try to run the DELETE > query, SQL grinds to a halt which causes my voice switches to > halt because they can't run the INSERT queries. Is this > because of table locking? An example delete query: > > DELETE from cdr WHERE accountcode='' > > Is there a way to make the DELETE query run at a lower > priority and allow the INSERTs? > > Here is the table description: > > mysql> describe cdr; > +-------------+--------------+------+-----+------------------- > --+-------+ > | Field | Type | Null | Key | Default > | Extra | > +-------------+--------------+------+-----+------------------- > --+-------+ > | uniqueid | varchar(32) | | | > | | > | userfield | varchar(255) | | | > | | > | accountcode | varchar(20) | | MUL | > | | > | src | varchar(80) | | MUL | > | | > | dst | varchar(80) | | | > | | > | dcontext | varchar(80) | | | > | | > | clid | varchar(80) | | | > | | > | channel | varchar(80) | | | > | | > | dstchannel | varchar(80) | | | > | | > | lastapp | varchar(80) | | | > | | > | lastdata | varchar(80) | | | > | | > | calldate | datetime | | | 0000-00-00 > 00:00:00 | | > | duration | int(11) | | | 0 > | | > | billsec | int(11) | | | 0 > | | > | disposition | varchar(45) | | | > | | > | amaflags | int(11) | | | 0 > | | > +-------------+--------------+------+-----+------------------- > --+-------+ > type is MyISAM > > indexes: > mysql> show index from cdr; > +-------+------------+----------+--------------+-------------+ > -----------+-------------+----------+--------+---------+ > | Table | Non_unique | Key_name | Seq_in_index | Column_name > | Collation > | | > Cardinality | Sub_part | Packed | Comment | > +-------+------------+----------+--------------+-------------+ > -----------+-------------+----------+--------+---------+ > | cdr | 1 | cdr_idx | 1 | src > | A | > NULL | NULL | NULL | | > | cdr | 1 | cdr_idx | 2 | dst > | A | > NULL | NULL | NULL | | > | cdr | 1 | cdr_idx | 3 | calldate > | A | > NULL | NULL | NULL | | > | cdr | 1 | cdr_idx | 4 | accountcode > | A | > NULL | NULL | NULL | | > | cdr | 1 | i1 | 1 | accountcode > | A | > NULL | NULL | NULL | | > | cdr | 1 | i1 | 2 | calldate > | A | > NULL | NULL | NULL | | > +-------+------------+----------+--------------+-------------+ > -----------+-------------+----------+--------+---------+ > > > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: > http://lists.mysql.com/[EMAIL PROTECTED] > > -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
