CREATE TABLE `a` ( `a1` VARCHAR(10) DEFAULT NULL, `b1` VARCHAR(10) DEFAULT NULL, `c1` VARCHAR(10) DEFAULT NULL ) ENGINE=INNODB DEFAULT CHARSET=utf8 CREATE TABLE `b` ( `a2` VARCHAR(10) DEFAULT NULL, `b2` VARCHAR(10) DEFAULT NULL ) ENGINE=INNODB DEFAULT CHARSET=utf8
创建出表,表内数据如下:
SQL语句执行结果图片在语句的下方
#inner join SELECT A.*,B.* FROM a INNER JOIN B ON a.a1=b.a2
#left join SELECT A.*,B.* FROM a LEFT OUTER JOIN b ON a.a1 = b.a2
#right join SELECT A.*,B.* FROM a RIGHT OUTER JOIN b ON a.a1 = b.a2
#full outer join union SELECT A.*,B.* FROM a LEFT OUTER JOIN b ON a.a1 = b.a2 UNION SELECT A.*,B.* FROM a RIGHT OUTER JOIN b ON a.a1 = b.a2
SELECT A.*, B.* FROM A,B
SELECT A.*,B.* FROM a JOIN b ON a.a1 = b.a2
默认是inner join