ALTER FUNCTION cannot be used to change a scalar-valued function to a table-valued function, or vice versa.
不能用ALTERFUNCTION将标量值函数更改为表值函数,反之亦然。
A scalar-valued function returns a single value, such as a string, integer, or bit value.
标量值函数返回单个值,例如字符串、整数或位值。
Here is a simple scalar-valued function that accesses data and returns an integer value
以下是访问数据并返回一个整数值的简单标量值函数