有没有一种方法可以给联接的结果表分配别名?
查询示例:
查询示例:
SELECT *
FROM t1
JOIN t2
ON t1.num = t2.num
AS result;
是的!
select result.*
from (SELECT *
FROM t1
JOIN t2
ON t1.num = t2.num) result
在涉及到内部表的相同列名时,你需要注意,否则你会在结果表中得到一个模棱两可的列错误。建议不要使用 select *,而是挑选出你需要的列。
SELECT *
FROM (
SELECT t1.id, t1.name, t2.category, t2.subcategory
FROM t1
INNER JOIN t2 ON t1.id=t2.id
) AS result
LEFT JOIN t3 ON result.id=t3.id
SELECT result.* FROM
(SELECT *
FROM t1
JOIN t2
ON t1.num = t2.num) AS result;
result.*
,那是什么? - Robert
result.*
,那是什么? - Robertselect c.* from (select o.goose, o.id, p.donkey from o join p on o.id=p.id) as c
。 - LordBaconPants