Friday, March 23, 2012

GetDate() in User Defined Functions, Parameters in View

1) Am I right in believing I can't access the GetDate() function from within
a table valued UDF ... ? That seems to be what the syntax checker is
telling me. Any suggested workarounds ?
2) I tried create a view which used a table valued UDF, with " getdate() "
as a parameter, in the view's from clause and the system didn't like that
either ... Any suggestions ? Are there ways of parameterizing a view ?
3) I need the view construct because I need to reference the returned
dataset from Analysis Services as a dimension. I prefer the UDF construct
(as opposed to selecting off a table with a where clause) because I don't
have to build a process to add new date records to the hypothetical table.
Performance isn't really an issue, because the only place the view is invoke
d
is in processing a cube in Analysis Services.
4) Some SQL
...
CREATE FUNCTION dbo.tfun_Date (
@.EndDate smalldatetime) --added when getdate didn't work
RETURNS @.DateTable table (
DateValue smalldatetime )
BEGIN
Declare @.DateIdx smalldatetime
Declare @.StartDate smalldatetime
Set @.StartDate = dbo.sfun_getdateparmref('DateDim1Start')
Set @.DateIdx = @.StartDate
--Set @.EndDate = getdate()
While @.DateIdx <= @.EndDate
Begin
Insert @.DateTable (DateValue) values (@.DateIdx)
Set @.DateIdx = DateAdd(dd,1, @.DateIdx)
End
Return
END
--
CREATE VIEW dbo.v_date
AS
SELECT top 10000 DateValue
, DateYYYY = Datepart(yyyy, DateValue)
, DateYYAbbrev = RIGHT(CONVERT(Char(4), Datepart(yy, DateValue)), 2)
, DateQtr = CASE Datepart(mm, DateValue)
WHEN 1 THEN 'Q1' WHEN 2 THEN 'Q1' WHEN 3 THEN 'Q1'
WHEN 4 THEN 'Q2' WHEN 5 THEN 'Q2' WHEN 6 THEN 'Q2' WHEN 7 THEN 'Q3' WHEN 8
THEN
'Q3' WHEN 9 THEN 'Q3' WHEN 10 THEN 'Q4' WHEN 11 THEN
'Q4' WHEN 12 THEN 'Q4' ELSE 'Er' END
, DateMM = Datepart(mm, DateValue)
, DateMMAbbrev = CASE Datepart(mm, DateValue)
WHEN 1 THEN 'Jan' WHEN 2 THEN 'Feb' WHEN 3 THEN 'Mar'
WHEN 4 THEN 'Apr' WHEN 5 THEN 'May' WHEN 6 THEN 'Jun' WHEN 7 THEN 'Jul' WHEN
8 THEN 'Aug' WHEN 9 THEN 'Sep' WHEN 10 THEN 'Oct'
WHEN 11 THEN 'Nov' WHEN 12 THEN 'Dec' ELSE 'Err' END
, DateDD = Datepart(dd,
DateValue), DowNbr = Datepart(dw, DateValue)
, DowAbbr = CASE Datepart(dw, DateValue)
WHEN 1 THEN 'Mon' WHEN 2 THEN 'Tue' WHEN 3 THEN 'Wed'
WHEN 4 THEN 'Thu' WHEN 5 THEN 'Fri' WHEN 6 THEN 'Sat' WHEN 7 THEN 'Sun' ELSE
'Err' END
, DayOfYear = DateDiff(d, CONVERT(smalldatetime, CONVERT(char(4),
Datepart(yyyy, DateValue)) + '01' + '01', 112), DateValue) + 1
, WeekOfYear = 1 + (DateDiff(d, CONVERT(smalldatetime, CONVERT(char(4),
Datepart(yyyy, DateValue)) + '01' + '01', 112), DateValue) + 7 - Datepart(dw
,
DateValue)) / 7
, WeekOfYearMondayDate = dateadd(dd, 1 - Datepart(dw, DateValue), DateValue)
, Workday = Case
When Datepart(dw, DateValue) > 5 then 'Weekend / Holiday'
When PublicHolidayFlag = 'H' then 'Weekend / Holiday'
Else 'Workday' End
, HolidayName
, PublicHolidayFlag
--THIS IS THE BOGUS LINE
FROM tfun_date( getdate() ) D
--ENDS HERE
Left outer Join ZR_PublicHols on D.DateValue = ZR_PublicHols.HolidayDate
order by DateValueYou could pass in to the UDF a new parameter which when called, you send it
the GETDATE/CURRENTTIMESTAMP function.
Then just use that new parameter as your getdate()
hth
Eric
MarcusW wrote:
> 1) Am I right in believing I can't access the GetDate() function from
> within a table valued UDF ... ? That seems to be what the syntax
> checker is telling me. Any suggested workarounds ?
> 2) I tried create a view which used a table valued UDF, with "
> getdate() " as a parameter, in the view's from clause and the system
> didn't like that either ... Any suggestions ? Are there ways of
> parameterizing a view ?
> 3) I need the view construct because I need to reference the returned
> dataset from Analysis Services as a dimension. I prefer the UDF
> construct (as opposed to selecting off a table with a where clause)
> because I don't have to build a process to add new date records to
> the hypothetical table. Performance isn't really an issue, because
> the only place the view is invoked is in processing a cube in
> Analysis Services.
> 4) Some SQL
> ...
> CREATE FUNCTION dbo.tfun_Date (
> @.EndDate smalldatetime) --added when getdate didn't work
> RETURNS @.DateTable table (
> DateValue smalldatetime )
> BEGIN
> Declare @.DateIdx smalldatetime
> Declare @.StartDate smalldatetime
> Set @.StartDate = dbo.sfun_getdateparmref('DateDim1Start')
> Set @.DateIdx = @.StartDate
> --Set @.EndDate = getdate()
> While @.DateIdx <= @.EndDate
> Begin
> Insert @.DateTable (DateValue) values (@.DateIdx)
> Set @.DateIdx = DateAdd(dd,1, @.DateIdx)
> End
> Return
> END
> --
> CREATE VIEW dbo.v_date
> AS
> SELECT top 10000 DateValue
> , DateYYYY = Datepart(yyyy, DateValue)
> , DateYYAbbrev = RIGHT(CONVERT(Char(4), Datepart(yy, DateValue)), 2)
> , DateQtr = CASE Datepart(mm, DateValue)
> WHEN 1 THEN 'Q1' WHEN 2 THEN 'Q1' WHEN 3 THEN
> 'Q1' WHEN 4 THEN 'Q2' WHEN 5 THEN 'Q2' WHEN 6 THEN 'Q2' WHEN 7 THEN
> 'Q3' WHEN 8 THEN
> 'Q3' WHEN 9 THEN 'Q3' WHEN 10 THEN 'Q4' WHEN
> 11 THEN 'Q4' WHEN 12 THEN 'Q4' ELSE 'Er' END
> , DateMM = Datepart(mm, DateValue)
> , DateMMAbbrev = CASE Datepart(mm, DateValue)
> WHEN 1 THEN 'Jan' WHEN 2 THEN 'Feb' WHEN 3 THEN
> 'Mar' WHEN 4 THEN 'Apr' WHEN 5 THEN 'May' WHEN 6 THEN 'Jun' WHEN 7
> THEN 'Jul' WHEN 8 THEN 'Aug' WHEN 9 THEN 'Sep'
> WHEN 10 THEN 'Oct'
> WHEN 11 THEN 'Nov' WHEN 12 THEN 'Dec' ELSE 'Err' END
> , DateDD = Datepart(dd,
> DateValue), DowNbr = Datepart(dw, DateValue)
> , DowAbbr = CASE Datepart(dw, DateValue)
> WHEN 1 THEN 'Mon' WHEN 2 THEN 'Tue' WHEN 3 THEN
> 'Wed' WHEN 4 THEN 'Thu' WHEN 5 THEN 'Fri' WHEN 6 THEN 'Sat' WHEN 7
> THEN 'Sun' ELSE 'Err' END
> , DayOfYear = DateDiff(d, CONVERT(smalldatetime, CONVERT(char(4),
> Datepart(yyyy, DateValue)) + '01' + '01', 112), DateValue) + 1
> , WeekOfYear = 1 + (DateDiff(d, CONVERT(smalldatetime,
> CONVERT(char(4), Datepart(yyyy, DateValue)) + '01' + '01', 112),
> DateValue) + 7 - Datepart(dw, DateValue)) / 7
> , WeekOfYearMondayDate = dateadd(dd, 1 - Datepart(dw, DateValue),
> DateValue) , Workday = Case
> When Datepart(dw, DateValue) > 5 then 'Weekend / Holiday'
> When PublicHolidayFlag = 'H' then 'Weekend / Holiday'
> Else 'Workday' End
> , HolidayName
> , PublicHolidayFlag
> --THIS IS THE BOGUS LINE
> FROM tfun_date( getdate() ) D
> --ENDS HERE
> Left outer Join ZR_PublicHols on D.DateValue =
> ZR_PublicHols.HolidayDate order by DateValue|||Marcus

> 1) Am I right in believing I can't access the GetDate() function from
within
> a table valued UDF ... ? That seems to be what the syntax checker is
> telling me. Any suggested workarounds ?
Correct. However, you can create a view that has the GetDate() in it and
then call that view from your UDF. This workaround may or may not continue
to work in future versions.

> 2) I tried create a view which used a table valued UDF, with " getdate() "
> as a parameter, in the view's from clause and the system didn't like that
> either ... Any suggestions ? Are there ways of parameterizing a view ?
An in-line table-valued UDF is a parameterized view. I think the problem
is still the GetDate() which cannot be a parameter to a UDF either. (Why
not? Because. Technically it is the issue of whether a function always
returns the same value or not.)
Russell Fields

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