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I wrote a SQL function to convert a datetime value in SQL to a friendlier "n Hours Ago" or "n Days Ago" etc type of message. And I was wondering if there was a better way to do it. (Yes I know "don't do it in SQL" but for design reasons I have to do it this way).Here is the function I've written:CREATE FUNCTION dbo.GetFriendlyDateTimeValue(@CompareDate DateTime)RETURNS nvarchar(48)ASBEGINDECLARE @Now DateTimeDECLARE @Hours intDECLARE @Suff nvarchar(256)DECLARE @Found bitSET @Found = 0SET @Now = getDate()SET @Hours = DATEDIFF(MI, @CompareDate, @Now)/60IF @Hours <= 1BEGINSET @Suff = 'Just Now'SET @Found = 1RETURN @SuffENDIF @Hours < 24BEGINSET @Suff = ' Hours Ago'SET @Found = 1ENDIF @Hours >= 8760 AND @Found = 0BEGINSET @Hours = @Hours / 8760SET @Suff = ' Years Ago'SET @Found = 1ENDIF @Hours >= 720 AND @Found = 0BEGINSET @Hours = @Hours / 720SET @Suff = ' Months Ago'SET @Found = 1ENDIF @Hours >= 168 AND @Found = 0BEGINSET @Hours = @Hours / 168SET @Suff = ' Weeks Ago'SET @Found = 1ENDIF @Hours >= 24 AND @Found = 0BEGINSET @Hours = @Hours / 24SET @Suff = ' Days Ago'SET @Found = 1ENDRETURN Convert(nvarchar, @Hours) + @SuffEND


Did you try this?I don't believe you can call 'getDate()' from a function in t-sql

2019年06月25日37分17秒

I did try it. Just tried it again on SQL 2005, 2008 and 2008R2 CTP. Works. GETDATE makes the function non-deterministic which limits its use a little. From SQL2000 BOL: "In Microsoft SQL Server 2000, nondeterministic functions cannot be specified in two types of Transact-SQL expressions: * An index cannot be created on a computed column if the computed_column_expression references any nondeterministic functions. * A clustered index cannot be created on a view if the view references any nondeterministic functions."

2019年06月25日37分17秒

Pretty sure this would not work on SQL 2000 since non-deterministic UDFs were new for 2005, but there are hack-arounds for that even. Worst case, you could mod the UDF to add a second datetime parameter were you'd pass in GETDATE().

2019年06月26日37分17秒