具有多个条件的 MySQL If 语句
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MySQL If statement with multiple conditions
提问by avinash chavan
I want to write IFstatement inside a Stored procedurein MySQL in the following way:
我想通过以下方式在 MySQL 中的IFaStored procedure中编写语句：
IF (exp1 and exp2 and exp3) or exp4
I know MySQL will treat IF()as a function call.
But I hope you got what I'm trying to achieve.
I am new to MySQL syntax.
我知道 MySQL 会将其IF()视为函数调用。但我希望你得到了我想要实现的目标。我是 MySQL 语法的新手。
回答by Jorge Campos
In a procedure the use of an IFis pretty straight forward:
在一个过程中， an 的使用IF非常简单：
IF (yourCondition [logical operator(OR, AND) another condition] ) THEN
So in a practical example:
所以在一个实际的例子中：
....
DECLARE m integer;
DECLARE n integer;
SET m = 1;
SET n = 0;
IF ((m>n AND m=1 AND n=0) OR m=n)THEN
some code here
END IF;
The evaluation of the conditions follows the parenthesis rule same as in a mathematical operation.
条件的评估遵循与数学运算中相同的括号规则。
You can refer to the Docs
你可以参考文档
