Is there a difference between @var := 0; and @var = 0; ?
@var：= 0之间有区别吗？和@var = 0; ？
With and without the colon? What does that do?
有没有结肠？那是做什么的？
1 个解决方案
#1
3
In the case of SET, they are synonymous:
在SET的情况下，它们是同义词：
SET @var := 1234;
SET @var = 1234;
But = acts as a conditional operator when used in a SELECT:
但是当在SELECT中使用时，=充当条件运算符：
SELECT @var := 1234; -- 1234
SELECT @var = 1234; -- 1
So it's generally best to stick to := for assignment to avoid confusion.
因此，通常最好坚持：=进行分配以避免混淆。
#1
3
In the case of SET, they are synonymous:
在SET的情况下，它们是同义词：
SET @var := 1234;
SET @var = 1234;
But = acts as a conditional operator when used in a SELECT:
但是当在SELECT中使用时，=充当条件运算符：
SELECT @var := 1234; -- 1234
SELECT @var = 1234; -- 1
So it's generally best to stick to := for assignment to avoid confusion.
因此，通常最好坚持：=进行分配以避免混淆。