How to transfer data from an ADO Recordset to Excel with automation
You can transfer the contents of an ADO recordset to a Microsoft Excel worksheet by automating Excel. The approach that you can use depends on the version of Excel you are automating. Excel 97, Excel 2000, and Excel 2002 have a CopyFromRecordset method that you can use to transfer a recordset to a range. CopyFromRecordset in Excel 2000 and 2002 can be used to copy either a DAO or an ADO recordset. However, CopyFromRecordset in Excel 97 supports only DAO recordsets. To transfer an ADO recordset to Excel 97, you can create an array from the recordset and then populate a range with the contents of that array.
This article discusses both approaches. The sample code presented illustrates how you can transfer an ADO recordset to Excel 97, Excel 2000, Excel 2002, Excel 2003, or Excel 2007.
The code sample provided below shows how to copy an ADO recordset to a Microsoft Excel worksheet using automation from Microsoft Visual Basic. The code first checks the version of Excel. If Excel 2000 or 2002 is detected, the CopyFromRecordset method is used because it is efficient and requires less code. However, if Excel 97 or earlier is detected, the recordset is first copied to an array using the GetRows method of the ADO recordset object. The array is then transposed so that records are in the first dimension (in rows), and fields are in the second dimension (in columns). Then, the array is copied to an Excel worksheet through assigning the array to a range of cells. (The array is copied in one step rather than looping through each cell in the worksheet.)
The code sample uses the Northwind sample database that is included with Microsoft Office. If you selected the default folder when you installed Microsoft Office, the database is located in:
\Program Files\Microsoft Office\Office\Samples\Northwind.mdb
If the Northwind database is located in a different folder on your computer, you need to edit the path of the database in the code provided below.
If you do not have the Northwind database installed on your system, you can use the Add/Remove option for Microsoft Office setup to install the sample databases.
Note The Northwind database is not installed when you install 2007 Microsoft Office. To obtain Northwind 2007, visit the following Microsoft Web site:
Steps to Create Sample
Start Visual Basic and create a new Standard EXE project. Form1 is created by default.
Add a CommandButton to Form1.
Click Referencesfrom the Project menu. Add a reference to the Microsoft ActiveX Data Objects 2.1 Library.
Paste the following code into the code section of Form1:
Private Sub Command1_Click() Dim cnt As New ADODB.Connection Dim rst As New ADODB.Recordset Dim xlApp As Object Dim xlWb As Object Dim xlWs As Object Dim recArray As Variant Dim strDB As String Dim fldCount As Integer Dim recCount As Long Dim iCol As Integer Dim iRow As Integer ' Set the string to the path of your Northwind database strDB ="c:\program files\Microsoft office\office11\samples\Northwind.mdb" ' Open connection to the database cnt.Open "Provider=Microsoft.Jet.OLEDB.4.0;" & _ "Data Source=" & strDB & ";" ''When using the Access 2007 Northwind database ''comment the previous code and uncomment the following code. 'cnt.Open "Provider=Microsoft.ACE.OLEDB.12.0;" & _ ' "Data Source=" & strDB & ";" ' Open recordset based on Orders table rst.Open "Select * From Orders", cnt ' Create an instance of Excel and add a workbook Set xlApp = CreateObject("Excel.Application") Set xlWb = xlApp.Workbooks.Add Set xlWs = xlWb.Worksheets("Sheet1") ' Display Excel and give user control of Excel's lifetime xlApp.Visible = True xlApp.UserControl = True ' Copy field names to the first row of the worksheet fldCount = rst.Fields.Count For iCol = 1 To fldCount xlWs.Cells(1, iCol).Value = rst.Fields(iCol - 1).Name Next ' Check version of Excel If Val(Mid(xlApp.Version, 1, InStr(1, xlApp.Version, ".") - 1)) > 8 Then 'EXCEL 2000,2002,2003, or 2007: Use CopyFromRecordset ' Copy the recordset to the worksheet, starting in cell A2 xlWs.Cells(2, 1).CopyFromRecordset rst 'Note: CopyFromRecordset will fail if the recordset 'contains an OLE object field or array data such 'as hierarchical recordsets Else 'EXCEL 97 or earlier: Use GetRows then copy array to Excel ' Copy recordset to an array recArray = rst.GetRows 'Note: GetRows returns a 0-based array where the first 'dimension contains fields and the second dimension 'contains records. We will transpose this array so that 'the first dimension contains records, allowing the 'data to appears properly when copied to Excel ' Determine number of records recCount = UBound(recArray, 2) + 1 '+ 1 since 0-based array ' Check the array for contents that are not valid when ' copying the array to an Excel worksheet For iCol = 0 To fldCount - 1 For iRow = 0 To recCount - 1 ' Take care of Date fields If IsDate(recArray(iCol, iRow)) Then recArray(iCol, iRow) = Format(recArray(iCol, iRow)) ' Take care of OLE object fields or array fields ElseIf IsArray(recArray(iCol, iRow)) Then recArray(iCol, iRow) = "Array Field" End If Next iRow 'next record Next iCol 'next field ' Transpose and Copy the array to the worksheet, ' starting in cell A2 xlWs.Cells(2, 1).Resize(recCount, fldCount).Value = _ TransposeDim(recArray) End If ' Auto-fit the column widths and row heights xlApp.Selection.CurrentRegion.Columns.AutoFit xlApp.Selection.CurrentRegion.Rows.AutoFit ' Close ADO objects rst.Close cnt.Close Set rst = Nothing Set cnt = Nothing ' Release Excel references Set xlWs = Nothing Set xlWb = Nothing Set xlApp = Nothing End Sub Function TransposeDim(v As Variant) As Variant ' Custom Function to Transpose a 0-based array (v) Dim X As Long, Y As Long, Xupper As Long, Yupper As Long Dim tempArray As Variant Xupper = UBound(v, 2) Yupper = UBound(v, 1) ReDim tempArray(Xupper, Yupper) For X = 0 To Xupper For Y = 0 To Yupper tempArray(X, Y) = v(Y, X) Next Y Next X TransposeDim = tempArray End Function
Press the F5 key to run the project. Form1 appears.
Click the CommandButton on Form1, and note that the contents of the Orders table is displayed in a new workbook in Excel.
For efficiency and performance, CopyFromRecordset is the preferred method. Because Excel 97 supports only DAO recordsets with CopyFromRecordset, if you attempt to pass an ADO recordset to CopyFromRecordset with Excel 97, you receive the following error:
Run-time error 430: Class does not support Automation or does not support expected interface. In the code sample, you can avoid this error by checking Excel's version so that you do not use CopyFromRecordset for the 97 version.
Note When using CopyFromRecordset, you should be aware that the ADO or DAO recordset you use cannot contain OLE object fields or array data such as hierarchical recordsets. If you include fields of either type in a recordset, the CopyFromRecordset method fails with the following error:
Run-time error -2147467259: Method CopyFromRecordset of object Range failed.
If Excel 97 is detected, use the GetRows method of the ADO recordset to copy the recordset into an array. If you assign the array returned by GetRows to a range of cells in the worksheet, the data goes across the columns instead of down the rows. For example, if the recordset has two fields and 10 rows, the array appears as two rows and 10 columns. Therefore, you need to transpose the array using your TransposeDim() function before assigning the array to the range of cells. When assigning an array to a range of cells, there are some limitations to be aware of:
The following limitations apply when assigning an array to an Excel Range object:
The array cannot contain OLE object fields or array data, such as hierarchical recordsets. Notice that the code sample checks for this condition and displays "Array Field" so that the user is made aware that the field cannot be displayed in Excel.
The array cannot contain Date fields that have a date prior to the year 1900. (See the "References" section for a Microsoft Knowledge Base article link.) Note that the code sample formats Date fields as variant strings to avoid this potential problem.
Note the use of the TransposeDim() function to transpose the array before the array is copied to the Excel worksheet. Instead of creating your own function to transpose the array, you can use Excel's Transpose function by modifying the sample code to assign the array to the cells as shown below:
xlWs.Cells(2, 1).Resize(recCount, fldCount).Value = _ xlApp.WorksheetFunction.Transpose(recArray)
If you decide to use Excel's Transpose method instead of the TransposeDim() function to transpose the array, you should be aware of the following limitations with the Transpose method:
- The array cannot contain an element that is greater than 255 characters.
- The array cannot contain Null values.
- The number of elements in the array cannot exceed 5461.
If the above limitations are not taken into consideration when you copy an array to an Excel worksheet, one of the following run-time errors may occur:
Run-time Error 13: Type Mismatch
Run-time Error 5: Invalid procedure
call or argument Run-time Error 1004: Application defined or object defined error
For additional information about limitations on passing arrays to various versions of Excel, click the following article number to view the article in the Microsoft Knowledge Base:
177991 XL: Limitations of Passing Arrays to Excel Using Automation
247412 INFO: Methods for Transferring Data to Excel from Visual Basic