在 Update 语句中使用表别名的好方法? [英] Good way to use table alias in Update statement?

问题描述

使用 SqlServer，并尝试更新同一个表中的行.我想使用表别名来提高可读性.这就是我目前的做法:

Using SqlServer, and trying to update rows from within the same table. I want to use a table alias for readability. This is the way I am doing it at the moment:

UPDATE ra 
SET ra.ItemValue = rb.ItemValue
FROM dbo.Rates ra, dbo.Rates rb
WHERE ra.ResourceID = rb.ResourceID
AND ra.PriceSched = 't8'
AND rb.PriceSched = 't9'

有更简单/更好的方法吗?

Are there easier / better ways?

推荐答案

UPDATE ra 
   SET ra.ItemValue = rb.ItemValue
  FROM dbo.Rates ra
 INNER JOIN dbo.Rates rb
         ON ra.ResourceID = rb.ResourceID
WHERE ra.PriceSched = 't8'
  AND rb.PriceSched = 't9';

这可能有助于提高性能.

This might help in improving performance.

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