删除此条件为真的行的存储过程：

Question

我需要每次自动删除行的存储过程，其中表paym中的列table1和table2都不为空。

下表中的示例： 表： paym

 ID        username        table1        Table2  
+-------+-------------+-------------+-----------+
|   1   |  John       |  Value      |    Value  |
+-------+-------------+-------------+-----------+
|   2   |  Alex       |  Null       |    Null   |
+-------+-------------+-------------+-----------+

条件为真：删除行后：

 ID        username        table1        Table2  
+-------+-------------+-------------+-----------+
|   2   |  Alex       |  Null       |    Null   |
+-------+-------------+-------------+-----------+

我的尝试是：（不工作）

CREATE PROCEDURE DeleteRow
        BEGIN
              DELETE
        FROM
            paym WHERE table1 and table2 IS NOT NULL ;
            END;

Answer 1

你的逻辑在这里，但语法是错误的。

在 WHERE 子句的每个字段之后，您必须指定一个条件，就像这样：

 CREATE PROCEDURE DeleteRow
         BEGIN
               DELETE
         FROM
             paym WHERE table1 IS NOT NULL AND table2 IS NOT NULL ;
             END;

Answer 2

您还可以使用COALESCE

CREATE PROCEDURE DeleteRow
BEGIN
DELETE FROM paym WHERE COALESCE(table1,table2) IS NOT NULL;
END;

Answer 3

 CREATE PROCEDURE DeleteRow
         BEGIN
               DELETE
         FROM
             paym WHERE table1 IS NOT NULL AND table2 IS NOT NULL ;
             END;

Answer 4

代码应该读取 table is not null and table 2 is not null，因为你需要在 and 语句之后有一个条件。