📜  union 和 union all 有什么区别 - 不管代码示例

📅  最后修改于: 2022-03-11 14:55:52.179000             🧑  作者: Mango

代码示例2
UNION ALL:
COMBINES THE RESULT OF 2 QUERY AND
DOESN'T REMOVE DUPLICATE ROWS
AND DOESN'T SORT BY FIRST COLUMN

UNION:
COMBINES THE RESULT OF 2 QUERY AND
REMOVES DUPLICATE ROWS AND
SORTS BY FIRST COLUMN