采用：
SELECt t1.id,t1.value,t2.value2 FROM table1 t1 LEFT JOIN table2 t2 ON t2.id = t1.idUNIOn SELECt t2.id,t1.value,t2.value2 FROM TABLE1 t1RIGHT JOIN TABLE2 t2 ON t2.id = t1.id
该
UNIOn操作者除去行/记录重复的，所以你必须列适当地定义/列表。
脚本：
DROP TABLE IF EXISTS `example`.`table1`;CREATE TABLE `example`.`table1` ( `id` int(10) unsigned NOT NULL default '0', `value` varchar(45) NOT NULL default '') ENGINE=InnoDB DEFAULT CHARSET=latin1;INSERT INTO table1 VALUES (1, 'a'), (2, 'c'), (3, 'e');DROP TABLE IF EXISTS `example`.`table2`;CREATE TABLE `example`.`table2` ( `id` int(10) unsigned NOT NULL default '0', `value2` varchar(45) NOT NULL default '') ENGINE=InnoDB DEFAULT CHARSET=latin1;INSERT INTO table2 VALUES (1, 'b'), (3, 'd'), (4, 'f');
编辑：上面的固定线
