SQL语句，空值

Question

我需要一些SQL语句的帮助，在下面的SQL语句工作的时候，但是如果closing_balance为null，我想添加将值设置为0.00 。

是否可以将此添加到以下语句中：

SqlCommand scGetPostings = new SqlCommand(@"
    SELECT 
      D1.dr, 
      D1.cr, 
      D1.asset_no, 
      (open_bal + dr - cr) AS closing_balance 
    FROM (SELECT 
            COALESCE(SUM(dr_amount), 0) AS dr, 
            COALESCE(SUM(cr_amount), 0) AS cr, 
            asset_no 
          FROM posting, sysasset 
          WHERE posting.asset_no = @AssetNumber 
            AND period >= asset_open_per 
          GROUP BY asset_no) AS D1, asset 
    WHERE D1.asset_no = asset.asset_no", DataAccess.AssetConnection);

Answer 1

您应该使用ISNULL函数作为语句：

ISNULL(open_bal + dr - cr, 0.0) as closing_balance

Answer 2

(ISNULL(open_bal, 0.0) + ISNULL(dr, 0.0) - ISNULL(cr, 0.0)) as closing_balance

Answer 3

尝试：

nvl(open_bal + dr - cr, 0.0) as closing_balance

sql_isnull