没有输入参数的 SQL 函数

Question

如何创建 SQL 函数 没有 输入参数

我收到以下代码的错误

create function function_name 
RETURN datetime AS 
BEGIN 
DECLARE @var datetime
SELECT  @var=CURRENT_TIMESTAMP 
RETURN @var
END

错误

> 
> Msg 156, Level 15, State 1, Procedure
> fx_getcurrent_date, Line 2 Incorrect
> syntax near the keyword 'RETURN'. Msg
> 178, Level 15, State 1, Procedure
> fx_getcurrent_date, Line 7 A RETURN
> statement with a return value cannot
> be used in this context.

Answer 1

您缺少您的 ()的。此外，它应该是 RETURNS第一次RETURN .

CREATE FUNCTION function_name
(
) 
RETURNS DATETIME 
AS 
BEGIN 
    DECLARE @var datetime 
    SELECT @var=CURRENT_TIMESTAMP 
    RETURN @var 
END