Slow Query - uses views

Question

Backend on the cloud using SQL Server Express 2008 R2 Frontend on Access 2013

I had a query that I recently had to add a subquery to to restrict the results. The query took about 1 second to run before, but now takes about 70+. I think the problem may be that I am using views in the query that are not indexed. I'm pretty new to this and don't use Access/SQL much, so apologies if i am missing something obvious here.

This is my query code:

SELECT DISTINCT vuSearch.PAID
    ,vuSearch.PDID
    ,ConcatAddress(Nz([Building_Name]), Nz([Building_No]), Nz([Street]), Nz([IndEst]), Nz([District]), Nz([Town]), Nz([Postcode])) AS Address
    ,vuSearch.Deal_Date
    ,vuSearch.Lease_End
    ,vuSearch.Break_Date
    ,vuSearch.Review_Date
    ,vuSearch.PropertyType
    ,vuSearch.Acting_For
    ,vuSearch.Landlord_Seller
    ,vuSearch.Tenant_Purchaser
    ,IIf(IsNull([vuSearch.GIA]), [vuSearch.NIA], [vuSearch.GIA]) AS MainArea
    ,vuDesc.Comments_Incentives
    ,tldDealSearch.Include
    ,vuSearch.Incomplete
FROM (
    vuSearch RIGHT JOIN tldDealSearch ON vuSearch.PDID = tldDealSearch.PDID
    )
LEFT JOIN vuDesc ON tldDealSearch.PDID = vuDesc.PDID
WHERE (
        (
            (vuSearch.PDID) IN (
                (
                    SELECT Max(v2.PDID)
                    FROM vuSearch AS v2
                    GROUP BY v2.PAID
                    )
                )
            )
        AND ((vuSearch.Incomplete) = False)
        );

I added indexes to the tldDealSearch table for the PDID and Include fields (I think I've done that right). When I looked at the views on the backend however I could not add indexes as the views are no schema bound.

Is there anything I can do or should be looking at to speed this up? I'm quite worried as right now there are only 300 records on the database - 70+ seconds?

I have checked everything on the 'Analyze performance' tool but not sure what to do next.

EDIT: Thanks for the fast responses guys.

NZ - This is the Access NullToZero function i believe, or what replaced it. http://www.techonthenet.com/access/functions/advanced/nz.php

ConcatAddress - This is a function I use to put all elements of an address together in a readable format for inclusion in a report.

Public Function ConcatAddress(strBuildingName As String, strBuildingNo As String, strStreet As String, _
strIndEstate As String, strDistrict As String, strTown As String, strPostcode As String) As String
    On Error GoTo ErrRoutine
    Dim strSQL As String
    If Len(strBuildingName) > 0 Then
        strSQL = strBuildingName
    End If
    If Len(strBuildingNo) > 0 Then
        If Len(strSQL) > 0 Then
            strSQL = strSQL & " " & strBuildingNo
        Else
            strSQL = strBuildingNo
        End If
    End If
    If Len(strStreet) > 0 Then
        If Len(strSQL) > 0 Then
            strSQL = strSQL & " " & strStreet & ","
        Else
            strSQL = strStreet
        End If
    End If
    If Len(strIndEstate) > 0 Then
        If Len(strSQL) > 0 Then
            strSQL = strSQL & " " & strIndEstate & ","
        Else
            strSQL = strIndEstate
        End If
    End If
    If Len(strDistrict) > 0 Then
        If Len(strSQL) > 0 Then
            strSQL = strSQL & " " & strDistrict & ","
        Else
            strSQL = strDistrict
        End If
    End If
    If Len(strTown) > 0 Then
        If Len(strSQL) > 0 Then
            strSQL = strSQL & " " & strTown
        Else
            strSQL = strTown
        End If
    End If
    If Len(strPostcode) > 0 Then
        If Len(strSQL) > 0 Then
            strSQL = strSQL & " " & strPostcode
        Else
            strSQL = strPostcode
        End If
    End If
    If Len(strSQL) > 0 Then
        ConcatAddress = strSQL
    Else
        ConcatAddress = ""
    End If
ErrExit:
    Exit Function
ErrRoutine:
    ConcatAddress = Empty
    Select Case Err
        Case 94
            'MsgBox "Postcode not found."
            Resume ErrExit
        Case Else
            MsgBox "The following error has occurred " & Err & " " & Err.Description
            Resume ErrExit
    End Select
End Function

'#'#'#'#'#'#'

EDIT

I was asked to post the execution plan for the query, but that is not available in access. I got a hack working that I think is close to what an execution plan is (couldn't get it to work with Access 2013 though).

[For Info] Add a key and string to the registry - HKEY_LOCAL_MACHINE\\SOFTWARE\\Wow6432Node\\Microsoft\\Jet\\4.0\\Engines
Add key 'Debug' and add string 'JETSHOWPLAN' - Set the value to ON to record (results should be in my documents or in location of database)

- Inputs to Query -
ODBC table 'vuSearch'
ODBC table 'vuSearch'
Table 'tldDealSearch'
ODBC table 'vuDesc'
- End inputs to Query -

01) Sort table 'vuDesc'
02) Outer Join table 'tldDealSearch' to result of '01)'
      using temporary index
      join expression "tldDealSearch.PDID=vuDesc.PDID"
1614631268) Remote SQL
03) Sort result of '02)'
04) Inner Join result of '02)' to result of '03)'
      using temporary index
      join expression "tldDealSearch.PDID=vuSearch.PDID"
      store result in temporary table

Seems to be alot of sorting going on so that must slow it down some. Hope this is what you were looking for.

EDIT
The Access JETSHOWPLAN does not give much detail so I transferred the tldSearchData table to the backend and ran the query there. I removed the concatAdderss (as it uses Access function) and also the IIF formula to determine which area to use. The resultant execution plans are below.

Actual: https://drive.google.com/file/d/0B5o8fYhuyQ0ZODZCWHNIaS1KZ1k/view?usp=sharing Estimated: https://drive.google.com/file/d/0B5o8fYhuyQ0ZU0lnRUhvaXVkc1k/view?usp=sharing
The query took 19 seconds to run directly from SQL (from the cloud server)

Answer 1

place your sql on the server as a view/proc, then call that instead of trying to troubleshoot performance in Access. Consider using a "passthrough" query, that will perform much, much faster compared to linked tables.