在SQL Server中将datetime转换为字符串/ varchar

Question

I have a view in SQL Server which uses dates to determine which tables to access data from. The problem is it only seems to work when given the date as a varchar like '20120423' .

So I am trying to dynamically create this date with GETDATE() instead of having to use the typed out version. When I run the top SELECT statement it returns '20120423' like I would expect but when I try to compare the two values they are not equal and the IF statement prints 'VALUES ARE NOT THE SAME' .

SELECT 
    '''' +CONVERT(VARCHAR(8), DateAdd(YY,-2,GETDATE()), 112) +'''' 

IF '''' +CONVERT(VARCHAR(8), DateAdd(YY,-2,GETDATE()), 112) +''''  = '20120423' 
BEGIN
    PRINT 'VALUES ARE THE SAME'
END
ELSE
BEGIN
   PRINT 'VALUES ARE NOT THE SAME'
END

I'm kind of lost as to where to go from here. Thanks for any help.

EDIT :
With the answers given then these two queries should be the same even though they are treated differently by my view.

SELECT * 
FROM DatesView 
WHERE Timestamp > CONVERT(VARCHAR(8), DateAdd(YY,-2,GETDATE()), 112)

SELECT * 
FROM DatesView 
WHERE Timestamp > '20120423'

The top one looks through all tables where the bottom one correctly only searches the necessary tables.

Answer 1

You're getting thrown off by the quote marks, just remove them they are unnecessary.

SELECT CONVERT(VARCHAR(8), DateAdd(YY,-2,GETDATE()), 112) 

IF CONVERT(VARCHAR(8), DateAdd(YY,-2,GETDATE()), 112)  = '20120423' 
BEGIN
    PRINT 'VALUES ARE THE SAME'
END
ELSE
BEGIN
   PRINT 'VALUES ARE NOT THE SAME'
END

Answer 2

Delete the first two ' . Try this. You are comparing '20120423'=20120423

SELECT '' +CONVERT(VARCHAR(8), DateAdd(YY,-2,GETDATE()), 112) +'' 

IF '' +CONVERT(VARCHAR(8), DateAdd(YY,-2,GETDATE()), 112) +''  = '20120423' 
BEGIN
    PRINT 'VALUES ARE THE SAME'
END
ELSE
BEGIN
   PRINT 'VALUES ARE NOT THE SAME'
END

Answer 3

You are adding apostrophes to the string, so your comparison is literally (replacing the string delimiters with brackets):

if ['20120423']  = [20120423]   

I think you want:

IF CONVERT(VARCHAR(8), DateAdd(YY,-2,GETDATE()), 112) = '20120423'

and/or

SELECT CONVERT(VARCHAR(8), DateAdd(YY,-2,GETDATE()), 112)