MS Access using forms in a pass-through query - sql

Question

I have a form named FietsAantDagen, a query named QueryFietsAantDagen and a textbox named Txtinput. I am trying to use a pass-through query to SQL Server and use a text form's input as a input in my query.
Query:
SELECT
Fiets_id,
Fiets_Type,
SUM(DATEDIFF(DAY, Huurovereenkomst_Begin_datum, Huurovereenkomst_Eind_datum)) AS AantalDagen
FROM
Fiets
INNER JOIN
HuurovereenkomstFiets
ON HuurovereenkomstFiets_Fiets_id = Fiets_id
INNER JOIN
Huurovereenkomst
ON Huurovereenkomst_id = HuurovereenkomstFiets_Huurovereenkomst_id
WHERE
YEAR(Huurovereenkomst_Begin_datum) = [Forms]![FietsAantDagen]![Txtinput]
AND YEAR(Huurovereenkomst_Eind_datum) = [Forms]![FietsAantDagen]![Txtinput]
GROUP BY
Fiets_id,
Fiets_Type
While running this query as a pass-through query I get the following error:
ODBC: Runtime error [Microsoft][SQL Server Native Client 11.0][SQL
Server]Incorrect syntax near the keyword 'WHERE'/ (#156)
Is the problem that I am using an Access text form value in a pass-through query, if so what can I do to solve it?
I read in another Overflow question you needed to add (), which I did and now I get the error:
JOIN-expression is not supported.
I'm going crazy...

Answer 1

If you don’t have direct use of SQL server, then likely best to create two pass though queries.
Query #1 – this is your raw SQL as you have
Eg:
SELECT
Fiets_id,
Fiets_Type,
SUM(DATEDIFF(DAY, Huurovereenkomst_Begin_datum,
Huurovereenkomst_Eind_datum)) AS AantalDagen
FROM
Fiets
INNER JOIN
HuurovereenkomstFiets
ON HuurovereenkomstFiets_Fiets_id = Fiets_id
INNER JOIN
Huurovereenkomst
ON Huurovereenkomst_id = HuurovereenkomstFiets_Huurovereenkomst_id
WHERE
YEAR(Huurovereenkomst_Begin_datum) = [StartYear]
AND YEAR(Huurovereenkomst_Eind_datum) = [EndYear]
GROUP BY
Fiets_id,
Fiets_Type
Query #2 – this is an application wide query you make that you can re-use over and over for any raw t-SQL (SQL server pass though). You then in code go like this:
Dim rst As DAO.Recordset
Dim strSQL As String
strSQL = CurrentDb.QueryDefs("MyQ1").SQL
srtSQL = Replace(strSQL, "[YearStart]", [Forms]![FietsAantDagen]![Txtinput])
strSQL = Replace(strSQL, "[YearEnd]", [Forms]![FietsAantDagen]![Txtinput])
With CurrentDb.QueryDefs("qryPassR")
.SQL = strSQL
.ReturnsRecords = True
Set rst = .OpenRecordset
End With
However, if you have the ability to use SQL server, and create a proc, then I would suggest you create store procedure like this:
CREATE PROCEDURE SelectDates
#StartYear int,
#EndYear int
AS
BEGIN
SET NOCOUNT ON;
SELECT
Fiets_id,
Fiets_Type,
SUM(DATEDIFF(DAY, Huurovereenkomst_Begin_datum, Huurovereenkomst_Eind_datum)) AS AantalDagen
FROM
Fiets
INNER JOIN
HuurovereenkomstFiets
ON HuurovereenkomstFiets_Fiets_id = Fiets_id
INNER JOIN
Huurovereenkomst
ON Huurovereenkomst_id = HuurovereenkomstFiets_Huurovereenkomst_id
WHERE
YEAR(Huurovereenkomst_Begin_datum) = #StartYear
AND YEAR(Huurovereenkomst_Eind_datum) = #EndYear
GROUP BY
Fiets_id,
Fiets_Type
END
Then in access, you use this:
Dim rst As DAO.Recordset
With CurrentDb.QueryDefs("qryPassR")
.SQL = "exec SelectDates " & [Forms]![FietsAantDagen]![Txtinput] & "," & _
[Forms]![FietsAantDagen]![Txtinput]
.ReturnsRecords = True
Set rst = .OpenRecordset
End With
So by passing parameters you reduce most of issues in regards to SQL injection.
Of course if you can’t create store procs, or don’t have permissions, then you have to adopt the first idea above. You can also of course in the first suggestion insert the raw SQL into the code editor, but I find using up an extra query to “just” hold the raw SQL, and then modifying the SQL into the 2nd pass-through query eliminates the need for messy SQL in the VBA code editor.

Answer 2

When you run a Pass-Through query, its SQL text gets sent to the DB server as-is, nothing is evaluated. So including [Forms]![FietsAantDagen]![Txtinput] in a Pass-Through query will never work.
You're on the right track with
SELECT * FROM fnFietsAantDagenPerJaar([Forms]![FietsAantDagen]![Txtinput])‌​
but you need to supply the parameter yourself, because (see above).
So you need to build the Pass-Through SQL, e.g. with this VBA procedure:
Private Sub txtInput_AfterUpdate()
Dim QD As DAO.QueryDef
Dim lYear As Long
' Make sure we pass a number to the SQL Server function
lYear = Val(Me!txtInput)
If lYear > 0 Then
Set QD = CurrentDb.QueryDefs("QueryFietsAantDagen")
QD.SQL = "SELECT * FROM fnFietsAantDagenPerJaar(" & lYear & ")"
Set QD = Nothing
' After changing the query SQL, requery the form
' This assumes that your form is bound to Pass-Through query QueryFietsAantDagen
Me.Requery
End If
End Sub

Answer 3

Pass-through queries run exclusively on the connected, external database engine, here being SQL Server, and does not see anything in MS Access, only everything in that external environment.
Consider adjusting pass-through query to avoid any MS Access evaluations and add year groupings to aggregate query. Then query this resultset in a local Access query filtering for needed year conditions using form values. Below adds table aliases for clarity (adjust if not correct).
Pass-Through (no WHERE clause, but extended SELECT and GROUP BY)
SELECT
f.Fiets_id,
f.Fiets_Type,
YEAR(h.Huurovereenkomst_Begin_datum) As BeginYear,
YEAR(h.Huurovereenkomst_Eind_datum) As EndYear,
SUM(DATEDIFF('d', h.Huurovereenkomst_Begin_datum,
h.Huurovereenkomst_Eind_datum)) AS AantalDagen
FROM
HuurovereenkomstFiets_LinkTable hf
INNER JOIN
Fiets_LinkTable f
ON hf.HuurovereenkomstFiets_Fiets_id = f.Fiets_id
INNER JOIN
Huurovereenkomst_LinkTable h
ON h.Huurovereenkomst_id = hf.HuurovereenkomstFiets_Huurovereenkomst_id
GROUP BY
f.Fiets_id,
f.Fiets_Type,
YEAR(h.Huurovereenkomst_Begin_datum),
YEAR(h.Huurovereenkomst_Eind_datum)
Local Query
SELECT
t.Fiets_id,
t.Fiets_Type,
t.AantalDagen
FROM
myPassThroughQuery t
WHERE t.BeginYear = [Forms]![FietsAantDagen]![Txtinput]
AND t.EndYear = [Forms]![FietsAantDagen]![Txtinput]
Alternatively, consider using linked tables from SQL Server (with same ODBC connection as pass-through) where Access can treat them as local tables. Hence, you can run your query using form date values. Do note you will have to convert syntax to adhere to Access' SQL dialect like DATEDIFF and JOIN parentheses. Performance may differ due to changed engines but test.
Linked Tables Local Query
SELECT
f.Fiets_id,
f.Fiets_Type,
SUM(DATEDIFF('d', h.Huurovereenkomst_Begin_datum,
h.Huurovereenkomst_Eind_datum)) AS AantalDagen
FROM
(HuurovereenkomstFiets_LinkTable hf
INNER JOIN
Fiets_LinkTable f
ON hf.HuurovereenkomstFiets_Fiets_id = f.Fiets_id)
INNER JOIN
Huurovereenkomst_LinkTable h
ON h.Huurovereenkomst_id = hf.HuurovereenkomstFiets_Huurovereenkomst_id
WHERE YEAR(h.Huurovereenkomst_Begin_datum) = [Forms]![FietsAantDagen]![Txtinput]
AND YEAR(h.Huurovereenkomst_Eind_datum) = [Forms]![FietsAantDagen]![Txtinput]
GROUP BY
f.Fiets_id,
f.Fiets_Type
To create linked tables automatically, use DoCmd.TransferDatabase. Otherwise, use the External Data / ODBC Database icon on ribbon and walk through setup wizard.
DoCmd.TransferDatabase acLink, "ODBC Database", _
"ODBC;DRIVER={SQL Server};Server=<ServerAddress>;Database=<DBname>;Trusted_Connection=Yes;", _
acTable, "HuurovereenkomstFiets", "HuurovereenkomstFiets_LinkedTable"