在 SQL Server 的更新语句中使用随机记录更新表? [英] Update table with random record in update statment in SQL Server?

问题描述

我有两张桌子.Table 1 大约有 80 行，Table 2 大约有 1000 万行.

I have two tables. Table 1 has about 80 rows and Table 2 has about 10 million.

我想用 Table 1 中的随机行更新 Table 2 中的所有行.我不希望所有行都在同一行.是否可以更新 Table 2 并让它为正在更新的每一行随机选择一个值?

I would like to update all the rows in Table 2 with a random row from Table 1. I don't want the same row for all the rows. Is it possible to update Table 2 and have it randomly select a value for each row it is updating?

这是我尝试过的，但它在每一行中放置了相同的值.

This is what I have tried, but it puts the same value in each row.

update member_info_test
set hostessid = (SELECT TOP 1 hostessId FROM hostess_test ORDER BY NEWID())

**已编辑

推荐答案

好吧，我认为这是我写过的最奇怪的查询之一，而且我认为这会非常慢.但是试一试:

Ok, I think that this is one of the weirdest query that I've wrote, and I think that this is gonna be terrible slow. But give it a shot:

UPDATE A
SET A.hostessid = B.hostessId
FROM member_info_test A
CROSS APPLY (SELECT TOP 1 hostessId
             FROM hostess_test 
             WHERE A.somecolumn = A.somecolumn
             ORDER BY NEWID()) B

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