交集
SELECT
a.*,
b.*
FROM
a
JOIN b ON
a.id = b.id;
差集
SELECT * FROM table_a ta
EXCEPT
SELECT * FROM table_b tb ;
-------------------------------------------
SELECT ta.* FROM table_a ta
WHERE ta.a NOT in (SELECT ta.a FROM table_a ta JOIN table_b tb ON ta.a=tb.a )
并集
SELECT * FROM table_a ta
union #或者union all
SELECT * FROM table_b tb ;
区别:
union 去重
union all 不去重