How To Retrieve a QueryDef from MS Access Using DAO

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Microsoft provides programming examples for illustration only, without warranty either expressed or implied. This includes, but is not limited to, the implied warranties of merchantability or fitness for a particular purpose. This article assumes that you are familiar with the programming language that is being demonstrated and with the tools that are used to create and to debug procedures. Microsoft support engineers can help explain the functionality of a particular procedure, but they will not modify these examples to provide added functionality or construct procedures to meet your specific requirements. This article uses the Northwind database included with Microsoft Office 95 Professional. If you selected the default options, the database is located in the \Msoffice\Access\Samples folder. If your Northwind database is located in a different folder, edit the provided code before running it.

In Microsoft Office 97, the default path for the Northwind database is \Program Files\Microsoft Office\Office\Samples\Northwind.mdb.

A QueryDef is created in Microsoft Access and saved with the database file. It consists of a query and may or may not include criteria.

NOTE: If you receive the "User-defined type not defined" error, activate a module sheet, click References on the Tools menu, and click Microsoft DAO 3.0 Object Library check box.

Retrieving the results of a QueryDef from Microsoft Access is a five step process as follows:

1. Establish a Database object.
2. Establish a QueryDef object.
3. Establish a Recordset Object.
4. Retrieve the Headers (if desired).
5. Retrieve the data from the table.

After the data is retrieved, you should close all the objects that you opened by issuing .Close commands.

   Sub GetQueryDef()
       'This sub will get data from an Existing QueryDef in the Northwind
       'database and place the data on sheet2.

         Dim Db As Database
         Dim Qd As QueryDef
         Dim Rs As Recordset
         Dim Ws As Object
         Dim i As Integer
      Dim Path as String

      'Set the Path to the database. This line is useful because
      'if your database is in another location, you just need to change
      'it here and the Path Variable will be used throughout the code.
      '
      'If you're using Microsoft Office 97, the line should read:
      '
      'Path = "C:\Program Files\Microsoft
      'Office\Office\Samples\Northwind.mdb"
      '
      Path = "C:\Msoffice\Access\Samples\Northwind.mdb"

       'Set Ws
       Set Ws = Sheets("Sheet1")

       'This set of code will activate Sheet1 and clear any existing data.
       'After clearing the data, it will select cell A1.
       Ws.Activate
       Range("A1").Activate
       Selection.CurrentRegion.Select
       Selection.ClearContents
       Range("A1").Select

       'Set the Database and QueryDef. This QueryDef exists in the
       'database.
       Set Db = Workspaces(0).OpenDatabase(Path, ReadOnly:=True, _
         Exclusive:=False)
       Set Qd = Db.QueryDefs("Invoices")

       'Create a new Recordset from the Query based on the stored
       'QueryDef.
       Set Rs = Qd.OpenRecordset()

       'This loop will collect the field names and place them in the first
       'row starting at "A1."
       For i = 0 To Rs.Fields.Count - 1
           Ws.Cells(1, i + 1).Value = Rs.Fields(i).Name
       Next

      'This line simply sets the font to bold for the headers.
      Ws.Range(Ws.Cells(1, 1), Ws.Cells(1, Rs.Fields.Count)).Font.Bold _
          =True

      'The next line will get the data from the recordset and copy it
      'into the Worksheet (Sheet1).

       Ws.Range("A2").CopyFromRecordset Rs

      'This next code set will just select the data region and auto-fit
      'the columns
       Sheets("Sheet1").Select
       Range("A1").Select
       Selection.CurrentRegion.Select
       Selection.Columns.AutoFit
       Range("A1").Select

       Qd.Close
       Rs.Close
       Db.Close

   End Sub