查询加入问题

Question

为什么此查询从两个表而不是仅从OVPM返回？

SELECT *
from OVPM M1
JOIN VPM2 M2 ON M2.DocNum = M1.DocNum
AND Canceled = 'N'
WHERE M1.DocNum = '2292'

Answer 1

因为你查询了一切*.如果您只需要数据OVPM- 请将其替换为M1.*