TSQL - FROM子查询中的TOP X? [英] TSQL - TOP X in FROM Subquery?

问题描述

有人可以告诉我一种过滤位于 FROM 子句中的子查询的方法吗?我希望它看起来像这样:

Can someone please enlighten me to a way to filter a subquery that is located in a FROM clause? I would like it to look something like this:

SELECT *
FROM TABLE_A
LEFT JOIN (TOP 8 TABLE_B) ON TABLE_B.id = TABLE_A.id

推荐答案

请试试这个:

SELECT 
column_names 
FROM 
TABLE_A A LEFT JOIN (SELECT TOP 8 column_names FROM TABLE_B) as B
on A.Id=B.ID

注意事项:

不要使用 *，因为它会导致性能限制.

Do not use * since it would lead to performance constraints.

如果您只关心 ID，则仅从 Table_B 获取 ID

IF you are concerned about just the ID then get only the ID from Table_B

HTH

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