I want to select something conditionally based on whether a bit field is true or false. This was the syntax that I originally tried:
我想根据位字段是真还是假来有条件地选择一些东西。这是我最初尝试的语法：
CASE WHEN isSoon THEN 'Soon' ELSE 'Not so soon' END As HowSoon
This makes sense to me since what follows the "WHEN" has to be a boolean expression, which isSoon is, as it's a bit field. However, this didn't work. What I had to do in the end was:
这对我来说很有意义，因为“WHEN”必须是一个布尔表达式，因为它是一个有点字段。但是，这不起作用。我最终要做的是：
CASE WHEN isSoon = 1 THEN 'Soon' ELSE 'Not so soon' END As HowSoon
This seems redundant to me... It's like writing if(isSoon == True) in a programming language instead of the more intuitive if(isSoon) and goes against the grain. Why is SQL set up like this? Is it because bit fields aren't truly boolean?
这对我来说似乎是多余的......就像在编程语言中编写if（isSoon == True）而不是更直观的if（isSoon）并且反对谷物。为什么SQL设置如此？是因为位字段不是真正的布尔值吗？
1 个解决方案
#1
13
Because the bit datatype is not a boolean type, it's a datatype used to optimize the bit storage.
由于位数据类型不是布尔类型，因此它是用于优化位存储的数据类型。
The fact that the string "true" and "false" can be converted to a bit can be misleading, however, quoting from MSDN , a bit is "An integer data type that can take a value of 1, 0, or NULL."
字符串“true”和“false”可以转换为位的事实可能会产生误导，但是，引用MSDN，有点是“可以取值为1,0或NULL的整数数据类型”。
#1
13
Because the bit datatype is not a boolean type, it's a datatype used to optimize the bit storage.
由于位数据类型不是布尔类型，因此它是用于优化位存储的数据类型。
The fact that the string "true" and "false" can be converted to a bit can be misleading, however, quoting from MSDN , a bit is "An integer data type that can take a value of 1, 0, or NULL."
字符串“true”和“false”可以转换为位的事实可能会产生误导，但是，引用MSDN，有点是“可以取值为1,0或NULL的整数数据类型”。