我无法让 CASE 语句在嵌套选择中工作。我想我已经很接近了,但我不能完全正确地理解语法。到目前为止,我已经尝试过:
SELECT l.*,
Credit = (
CASE WHEN ISNULL(M.POSTCODE,'') <> '' THEN
sum(Credit) from Balance cb Where LEFT(LTrim(cb.AccountHolder),4) LIKE LEFT(LTrim(m.Company),4)
ELSE
sum(Credit) from Balance cb Where LEFT(LTrim(cb.AccountHolder),4) LIKE LEFT(LTrim(m.Company),4)
END
)
FROM live l INNER JOIN master m on m.ClientID = L.ClientID
WHERE ClientID = 12345
并且:
SELECT l.*,
(SELECT
CASE WHEN ISNULL(M.POSTCODE,'') <> '' THEN
sum(Credit) from Balance cb Where LEFT(LTrim(cb.AccountHolder),4) LIKE LEFT(LTrim(m.Company),4)
ELSE
sum(Credit) from Balance cb Where LEFT(LTrim(cb.AccountHolder),4) LIKE LEFT(LTrim(m.Company),4)
END
) AS Credit
FROM live l INNER JOIN master m on m.ClientID = L.ClientID
WHERE ClientID = 12345
这似乎与http://msdn.microsoft.com/en-us/library/ms181765.aspx上的 MSDN 示例相匹配。我错过了什么吗?