SQL Server-如何带回函数中的WHILE BREAK循环以及其结果？

Question

I have this bit of code which works

DECLARE @IntDte as INT
SET @IntDte = 1
WHILE @IntDte <=10
BEGIN
IF (SELECT isworkday FROM Calendar WHERE date=CAST(FLOOR(CAST(GETDATE()-@IntDte As float))As datetime))= 1 -- 1 is a workday 0 is a weekend
            BREAK
            ELSE
        SET @IntDte= @IntDte + 1        
END
PRINT @IntDte

This brings back the last an integer that will bring back the last working day (ie if it is Monday today the loop will bring back 4 because that's Friday.

What I want though which I'm struggling is to build this into a function to get the date. I have this so far but its not correct -

Create FUNCTION [dbo].[PREVIOUSWORKINGDAY]
RETURNS datetime
AS BEGIN
DECLARE @PWD as datetime

SET @PWD = GetDate() -
(DECLARE @IntDte as INT
SET @IntDte = 2
WHILE @IntDte <=10
BEGIN
IF (SELECT isworkday FROM Calendar WHERE date=CAST(FLOOR(CAST(GETDATE()-@IntDte As float))As datetime))= 1 -- 1 is a workday 0 is a weekend
            BREAK
            ELSE
        SET @IntDte= @IntDte + 1        
END
RETURN)

RETURN @PWD
END

Would anyone be able to point out where im going wrong, at current im getting syntax errors -

Msg 102, Level 15, State 1, Procedure PREVIOUSWORKINGDAY, Line 2 Incorrect syntax near 'RETURNS'.

Msg 156, Level 15, State 1, Procedure PREVIOUSWORKINGDAY, Line 7 Incorrect syntax near the keyword 'DECLARE'.

Msg 102, Level 15, State 1, Procedure PREVIOUSWORKINGDAY, Line 16 Incorrect syntax near ')'.

Msg 178, Level 15, State 1, Procedure PREVIOUSWORKINGDAY, Line 18 A RETURN statement with a return value cannot be used in this context.

Im assuming I have some stuff in the wrong place but not sure where it should go.

thanks

Answer 1

The problem with your SQL looks to be that you have two return statements and you are trying to embed declare statements. Here is how I'd re-write your version:

Create FUNCTION [dbo].[PREVIOUSWORKINGDAY]
RETURNS datetime
AS BEGIN
    DECLARE @PWD as datetime
    DECLARE @IntDte as INT

    SET @IntDte = 2
    WHILE @IntDte <=10
    BEGIN
        IF (SELECT isworkday FROM Calendar WHERE date=CAST(FLOOR(CAST(GETDATE()-@IntDte As float))As datetime))= 1 -- 1 is a workday 0 is a weekend
            BREAK
        ELSE
            SET @IntDte= @IntDte + 1        
    END

    SET @PWD = GetDate() - IntDte

    RETURN @PWD
END

This is how I would write it though.

Create FUNCTION [dbo].[PREVIOUSWORKINGDAY]
RETURNS datetime
AS BEGIN
    DECLARE @PWD as datetime

        SELECT @PWD=Max(date)
        FROM Calendar
        WHERE isworkday=1
        AND date<CONVERT(DATE,GETDATE())

    RETURN @PWD
END