请看以下SQL语句:
SELECT datediff("d", MAX(invoice.date), Now) As Date_Diff
, MAX(invoice.date) AS max_invoice_date
, customer.number AS customer_number
FROM invoice
INNER JOIN customer
ON invoice.customer_number = customer.number
GROUP BY customer.number
如果添加了以下内容:
HAVING datediff("d", MAX(invoice.date), Now) > 365
这是否只是排除Date_Diff <= 365的行?
HAVING子句在这里应该有什么效果?
编辑:我没有遇到这里答案所说的情况。mdb的副本位于http://hotfile.com/dl/40641614/2353dfc/test.mdb.html(没有宏或病毒)。VISDATA.EXE用于执行查询。
编辑2:我认为问题可能是VISDATA,因为我通过DAO获得了不同的结果。