过滤掉查询中的NULL

Question

以下子查询返回一些空值和一些值。我想选择非空行，我该怎么做？

        ,(select distinct LEDGERTABLE.ACCOUNTNAME
    FROM ledgertrans 
    Where Salesline.SalesID = #tempCMs.SALESID and salesline.DIMENSION = 
        (Select top 1 Ledgertrans.Dimension
        From LedgerTrans
            Where Ledgertrans.Voucher = #tempCms.InvoiceID and LedgerTrans.AccountNum = Ledgertable.Accountnum)
 ) As 'Account'

由于

Answer 1

使用NULL

过滤IS NOT NULL

试试这个：

(select distinct LEDGERTABLE.ACCOUNTNAME
    FROM ledgertrans 
    Where Salesline.SalesID = #tempCMs.SALESID and salesline.DIMENSION = 
        (Select top 1 Ledgertrans.Dimension
        From LedgerTrans
            Where Ledgertrans.Voucher = #tempCms.InvoiceID 
            and LedgerTrans.AccountNum = Ledgertable.Accountnum
            AND LEDGERTABLE.ACCOUNTNAME IS NOT NULL)
 ) As 'Account'

NULL值未使用相等性测试（!= NULL）进行过滤，因为NULL值未知，因此无法确定相等性。

Answer 2

将AND LEDGERTABLE.ACCOUNTNAME IS NOT NULL添加到您的WHERE子句中。