Given this table, I want to count the number of distinct targetranges. CREATE TABLE job ( job_id int(10) unsigned NOT NULL auto_increment, customer_id int(10) unsigned NOT NULL default '0', scanner_id int(10) unsigned NOT NULL default '0', status_id int(10) unsigned NOT NULL default '0', changed timestamp(14) NOT NULL, targetrange char(255) default NULL, force_exit tinyint(1) unsigned NOT NULL default '0', PRIMARY KEY (job_id), KEY status_id (status_id) ) TYPE=InnoDB;
I tried "select distinct targetrange from job;" and I do get "273" rows. But I would have to use PHP's mysql_num_rows() to get that. I don't need all the rows returned however, just the count(), so I think this method is wasteful and probably will get slower as the db fills up with millions of rows. mysql> select count(1) from job; +----------+ | count(1) | +----------+ | 351 | +----------+ Is more of what I want, but how do I combine that with DISTINCT to get something like: +----------+ | count(1) | +----------+ | 273 | +----------+ And also, should I make targetrange an index too to help speed up the query or will it not matter? --------------------------------------------------------------------- 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
