The two querys's logic are different.Which is you need? ----- Original Message ----- From: "afan pasalic" <[EMAIL PROTECTED]> To: <mysql@lists.mysql.com> Sent: Wednesday, June 04, 2008 5:50 AM Subject: what's better query?
> Hi, > > I have two tables, "people" and "membership". Both have email column > (different column names though). > > CREATE TABLE `people` ( > `person_id` int(8) unsigned NOT NULL, > `address_id` int(8) default NULL, > `first_name` varchar(45) NOT NULL, > `last_name` varchar(45) NOT NULL, > `email` varchar(50) default NULL, > PRIMARY KEY (`person_id`), > ) ENGINE=MyISAM DEFAULT CHARSET=latin1 > > > CREATE TABLE `membership` ( > `person_id` int(8) unsigned NOT NULL, > `organization_id` int(8) unsigned NOT NULL, > `email_address` varchar(45) default NULL, > `title` varchar(45) default NULL, > `department` varchar(45) default NULL, > `direct_phone` varchar(10) default NULL, > PRIMARY KEY (`person_id`,`organization_id`), > KEY `index_email` (`email_address`), > ) ENGINE=MyISAM DEFAULT CHARSET=latin1 > > > I need to check if entered email address exists in either one of these > two tables. > I made these two queries. Which one is better one? > > ( > SELECT p.person_id, p.email, p.first_name, p.last_name > FROM people p > WHERE email='".$email."' > ) > UNION > ( > SELECT m.person_id, m.email_address as email, p.first_name, p.last_name > FROM membership m > LEFT JOIN people p ON p.person_id=m.person_id > WHERE m.email_address='".$email."' > ) > > or: > > SELECT p.person_id, p.email, p.first_name, p.last_name, m.email_address > FROM people p, membership m > WHERE (p.email='".$email."' OR m.email_address='".$email."') > AND p.person_id=m.person_id > > > > Thanks. > > -afan > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] > >
