Calendar query from table [duplicate] - ms-access

Question

MS Access 2003.
I need to get the array of dates which are located in the range start_date to end_date.
I not found such function in standard set of MS Access.
I write VBA function:
Option Compare Database
' © Andrey Bushman, 2014
' Get the array of dates which are located in the range start_date to end_date.
' The result is an array of Date items.
Public Function GetDays(start_date As Date, end_date As Date)
If start_date > end_date Then
' end_date can't be less than start_date.
GetDays = Null
Exit Function
End If
Dim size As Long
size = end_date - start_date
Dim result() As Date
ReDim result(size) ' including the range boundaries.
Dim index As Long
index = 0
Dim day As Date
day = start_date
Do While day <= end_date
result(index) = day
day = day + 1
index = index + 1
Loop
GetDays = result
End Function
My SQL query:
SELECT tbChecks.CheckId, tbChecks.[In], tbChecks.Back, GetDays([In],[Back]) AS DayItem FROM tbChecks;
But I get an #Error text in the DayItem field for each record.
This is not work too:
SELECT GetDays(CDate("01.01.2014"), CDate("05.01.2014")) as DayItem;
I get the error: Data type mismatch in criteria expression. (Error 3464).
How can I solve it?

Answer 1

You are getting errors because your VBA function is returning an array of Date values but the Access Database Engine does not have an Array field type. Even if it did, you would wind up with a single row containing an array of dates and (according to the comments to the question) you want each date in a separate row.
You should be able to accomplish your goal without using VBA at all if you create a "Numbers" table with sequential integer values from 0 to a sufficiently large value, e.g.,
n
----
0
1
2
3
...
998
999
1000
and then use a query like this:
SELECT DateAdd("d",n,#2014-01-01#) AS DayItem
FROM Numbers
WHERE n <= DateDiff("d",#2014-01-01#,#2014-01-05#)
returning
DayItem
----------
2014-01-01
2014-01-02
2014-01-03
2014-01-04
2014-01-05