Sunday, 6 October 2013



Running Access Queries From Excel Using VBA


Introduction



Two weeks ago I published a VBA code for retrieving values from DBF (database) files. The next days I received some e-mail requests about doing the same, but for Access databases. More precisely, two blog readers (Josh and Maria) asked me to write two different VBA codes for running Access queries directly from Excel. I decided to “answer” in both requests by writing this post, since both of them are related to the same subject: Access queries.

In the next paragraph you will find two VBA code snippets that can be used from Excel in order to retrieve data from an Access database. The idea behind both codes is the same:
  • Create and open a connection to the Access database.
  • Create a recordset that will contain the query results.
  • Create the necessary SQL select statement or set the query name.
  • Open the recordset.
  • If the recordset is not empty, write its data into Excel.
  • Close both recordset and connection.
Both codes have many similarities and share a lot of code lines. Their main difference, however, is in the query part. The first code (CreateAndRunQuery) creates the query on the fly, while the second one (RunExistingQuery) uses an existing query of the database.



VBA code



Both macros below use the Sample.accdb database which is located in the same folder with the workbook. First the CreateAndRunQuery macro is presented, which runs a query on the Customers table of the database, retrieving information (names, addresses etc.) from all the customers from Canada.

Option Explicit 

Sub CreateAndRunQuery()
    
    '------------------------------------------------------------------------------------------
    'This macro opens the Sample.accdb database, creates and runs an SQL query (filtering
    'all the customers from Canada). Then, it copies selected fields back in the Excel sheet.
    'The code uses late binding, so no reference to external library is required.
    
    'Written By:    Christos Samaras
    'Date:          05/10/2013
    'Last Updated:  29/11/2014
    'E-mail:        xristos.samaras@gmail.com
    'Site:          http://www.myengineeringworld.net
    '------------------------------------------------------------------------------------------

    'Declaring the necessary variables.
    Dim con         As Object
    Dim rs          As Object
    Dim AccessFile  As String
    Dim strTable    As String
    Dim SQL         As String
    Dim i           As Integer
            
    'Disable screen flickering.
    Application.ScreenUpdating = False
    
    'Specify the file path of the accdb file. You can also use the full path of the file like:
    'AccessFile = "C:\Users\Christos\Desktop\Sample.accdb"
    AccessFile = ThisWorkbook.Path & "\" & "Sample.accdb"
    
    'Set the name of the table you want to retrieve the data.
    strTable = "Customers"
    
    On Error Resume Next
    'Create the ADODB connection object.
    Set con = CreateObject("ADODB.connection")
    'Check if the object was created.
    If Err.Number <> 0 Then
        MsgBox "Connection was not created!", vbCritical, "Connection Error"
        Exit Sub
    End If
    On Error GoTo 0
    
    'Open the connection.
    con.Open "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & AccessFile
    
    'Create the SQL statement to retrieve the data from table.
    'Get the necessary information (first name etc.) for all the Canadian customers.
    SQL = "SELECT FirstName, LastName, Address, City, Phone FROM " & strTable & " WHERE COUNTRY='Canada'"
    
    On Error Resume Next
    'Create the ADODB recordset object.
    Set rs = CreateObject("ADODB.Recordset")
    'Check if the object was created.
    If Err.Number <> 0 Then
        'Error! Release the objects and exit.
        Set rs = Nothing
        Set con = Nothing
        'Display an error message to the user.
        MsgBox "Recordset was not created!", vbCritical, "Recordset Error"
        Exit Sub
    End If
    On Error GoTo 0
         
    'Set thee cursor location.
    rs.CursorLocation = 3 'adUseClient on early  binding
    rs.CursorType = 1 'adOpenKeyset on early  binding
    
    'Open the recordset.
    rs.Open SQL, con
    
    'Check if the recordet is empty.
    If rs.EOF And rs.BOF Then
        'Close the recordet and the connection.
        rs.Close
        con.Close
        'Release the objects.
        Set rs = Nothing
        Set con = Nothing
        'Enable the screen.
        Application.ScreenUpdating = True
        'In case of an empty recordset display an error.
        MsgBox "There are no records in the recordset!", vbCritical, "No Records"
        Exit Sub
    End If
    
    'Copy the recordset headers.
    For i = 0 To rs.Fields.Count - 1
        Sheets("New Query").Cells(1, i + 1) = rs.Fields(i).Name
    Next i
    
    'Write the query values in the sheet.
    Sheets("New Query").Range("A2").CopyFromRecordset rs
    
    'Close the recordet and the connection.
    rs.Close
    con.Close
    
    'Release the objects.
    Set rs = Nothing
    Set con = Nothing
    
    'Adjust the columns' width.
    Sheets("New Query").Columns("A:E").AutoFit
    
    'Enable the screen.
    Application.ScreenUpdating = True

    'Inform the user that the macro was executed successfully.
    MsgBox "The Canadian customers were successfully retrieved from the '" & strTable & "' table!", vbInformation, "Done"

End Sub

Here is the RunExistingQuery macro, which runs the existing qrRegions query. The particular query counts the number of customers from each region on the Customers table.

Option Explicit

Sub RunExistingQuery()
    
    '------------------------------------------------------------------------------------
    'This macro opens the Sample.accdb database and runs the (existing) qrRegions query
    '(counting the number of customers from each region, based on table Customers).
    'Then, it copies all the query results back in the Excel sheet.
    'The code uses late binding, so no reference to external library is required.
    
    'Written By:    Christos Samaras
    'Date:          05/10/2013
    'Last Updated:  29/11/2014
    'E-mail:        xristos.samaras@gmail.com
    'Site:          http://www.myengineeringworld.net
    '------------------------------------------------------------------------------------

    'Declaring the necessary variables.
    Dim con         As Object
    Dim rs          As Object
    Dim AccessFile  As String
    Dim strQuery    As String
    Dim i           As Integer
            
    'Disable screen flickering.
    Application.ScreenUpdating = False
    
    'Specify the file path of the accdb file. You can also use the full path of the file like:
    'AccessFile = "C:\Users\Christos\Desktop\Sample.accdb"
    AccessFile = ThisWorkbook.Path & "\" & "Sample.accdb"
    
    'Set the name of the query you want to run adn retrieve the data.
    strQuery = "qrRegions"
    
    On Error Resume Next
    'Create the ADODB connection object.
    Set con = CreateObject("ADODB.connection")
    'Check if the object was created.
    If Err.Number <> 0 Then
        MsgBox "Connection was not created!", vbCritical, "Connection Error"
        Exit Sub
    End If
    On Error GoTo 0
    
    'Open the connection.
    con.Open "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & AccessFile
    
    On Error Resume Next
    'Create the ADODB recordset object.
    Set rs = CreateObject("ADODB.Recordset")
    'Check if the object was created.
    If Err.Number <> 0 Then
        'Error! Release the objects and exit.
        Set rs = Nothing
        Set con = Nothing
        'Display an error message to the user.
        MsgBox "Recordset was not created!", vbCritical, "Recordset Error"
        Exit Sub
    End If
    On Error GoTo 0
         
    'Set thee cursor location.
    rs.CursorLocation = 3 'adUseClient on early  binding
    rs.CursorType = 1 'adOpenKeyset on early  binding
    
    'Open the recordset.
    rs.Open strQuery, con
    
    'Check if the recordet is empty.
    If rs.EOF And rs.BOF Then
        'Close the recordet and the connection.
        rs.Close
        con.Close
        'Release the objects.
        Set rs = Nothing
        Set con = Nothing
        'Enable the screen.
        Application.ScreenUpdating = True
        'In case of an empty recordset display an error.
        MsgBox "There are no records in the recordset!", vbCritical, "No Records"
        Exit Sub
    End If
    
    'Copy the recordset headers.
    For i = 0 To rs.Fields.Count - 1
        Sheets("Existing Access Query").Cells(1, i + 1) = rs.Fields(i).Name
    Next i
    
    'Write the query values in the sheet.
     Sheets("Existing Access Query").Range("A2").CopyFromRecordset rs
    
    'Close the recordet and the connection.
    rs.Close
    con.Close
    
    'Release the objects.
    Set rs = Nothing
    Set con = Nothing
    
    'Adjust the columns' width.
    Columns("A:B").AutoFit
    
    'Enable the screen.
    Application.ScreenUpdating = True

    'Inform the user that the macro was executed successfully.
    MsgBox "All data were  successfully retrieved from the '" & strQuery & "' query!", vbInformation, "Done"

End Sub

Both codes use late binding, so no reference to external library is required.



Downloads



Download


The zip file contains an Excel workbook that contains the two macros presented above, as well as a sample Access database. The workbook can be opened with Excel 2007 or newer. 



Read also



Read DBF Files Using VBA
Export A Large Access Table/Query To Excel

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Mechanical Engineer (Ph.D. cand.), M.Sc. Cranfield University, Dipl.-Ing. Aristotle University, Thessaloniki - Greece.
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