我要问:
SELECT
offer,
(SELECT
AVG(offer)
FROM
project_bids
) as var1
FROM
`project_bids`
WHERE
offer > var1
It causes "#1054 - Unknown column var1 in where clause " error. Can anybody expalain why gives that error ? (i know working sql but i want to learn why it fails)
页: 1
the where statement does not have access to columns created in the select statement
原文如下:
www.un.org/Depts/DGACM/index_french.htm WHERE offer >
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