我试着进行下面的查询:SELECT AS问题
SELECT t1.[user1], t1.[user2],
(CAST(t1.[total_event_duration] AS DECIMAL))/(CAST (t2.[total_events_duration] AS DECIMAL)) AS buddy_strength
FROM [CDRs].[dbo].[aggregate_monthly_events] AS t1
INNER JOIN [CDRs].[dbo].[user_monthly_stats] AS t2
ON t1.[user1] = t2.[user1]
WHERE buddy_strength > 0.02
但它返回一个错误“无效的列名称buddy_strength'”
有谁知道如何解决上面的查询?
适用于普遍适用的快速修复。 – egrunin 2010-10-22 13:47:37
+1与重复整个表达式相比,这会有性能优势吗? – Patrick 2010-10-22 14:17:45
@帕特里克:不,在这种情况下,它是有效的短路 – gbn 2010-10-22 16:51:49