Sql 简明教程
SQL - Logical Functions
SQL logical functions 主要用于检查(或测试)某些条件的真假。逻辑函数对对象和表达式执行逻辑运算或比较,并返回一个布尔值:
SQL logical functions are used primarily for checking (or testing) the truth of some conditions. A logical function performs a logical operation or comparison on objects and expressions and returns a boolean value −
Sr.No. |
Function & Description |
1 |
CHOSE()Returns a item from the list at the specified index value. |
2 |
IIF()Returns a one of two values, depending on the boolean-expression. |
3 |
NULLIF()Returns NULL if both expressions are equal. |