MySQL如何多表合并查询？

Question

SELECT * FROM question, WHERE title LIKE '%的%' OR selection LIKE '%的%';
SELECT * FROM doctortype WHERE title LIKE '%的%' OR selection LIKE '%的%';
SELECT * FROM teachertype WHERE title LIKE '%的%' OR selection LIKE '%的%';
SELECT * FROM computertype WHERE title LIKE '%的%' OR selection LIKE '%的%';

我想同时一条语句得到这四个表的数据要如何写？

Answer 1

使用union all

Answer 2

数据都放到ES里查询

Answer 3

# union all
select * from t_file where id = 1 union all select * from t_file where id = 10

# a.*,b.*
select a.*,b.* from (select * from a) as a,(select * from b) as b