鸣谢: https://blog.csdn.net/plg17/article/details/78758593
CREATE TABLE `a_table` (
`a_id` int(11) DEFAULT NULL,
`a_name` varchar(10) DEFAULT NULL,
`a_part` varchar(10) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8
CREATE TABLE `b_table` (
`b_id` int(11) DEFAULT NULL,
`b_name` varchar(10) DEFAULT NULL,
`b_part` varchar(10) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8
insert into b_table value(2,"老王","秘书部");
insert into b_table value(3,"老张","设计部");
insert into b_table value(5,"老刘","人事部");
insert into b_table value(6,"老黄","生产部");
insert into a_table value(1,"老潘","总裁部");
insert into a_table value(2,"老王","秘书部");
insert into a_table value(3,"老张","设计部");
insert into a_table value(4,"老李","运营部");
image.png
内连接:
select * from a_table a inner join b_table b on a.a_id = b.b_id;
外连接:
左连接:
select * from a_table a left join b_table bon a.a_id = b.b_id;
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