PRB: Appending Fields to a Recordset Generates an Error

• ActiveX Data Objects (ADO), versions 2.0, 2.01, 2.1

SYMPTOMS

Trying to append Fields to an opened Recordset generates the following run-time error:

Run-time error '3219':
The operation requested by the application is not allowed in this context.

CAUSE

From the ADO Help:

"Calling the fields.Append method for an open Recordset or a Recordset where the ActiveConnection property has been set, will cause a run-time error. You can only append fields to a Recordset that is not open and has not yet been connected to a data source. Typically, these are new Recordset objects that you create with the CreateRecordset method or by explicitly assigning a new Recordset object to an object variable."

RESOLUTION

There are two workarounds to getting additional Fields appended to a Recordset object.

1. Create the Recordset from scratch, creating all the necessary Fields, then open the custom recordset and populate it with the necessary data:




Dim rst As New ADODB.Recordset

rst.Fields.Append "xx1", adInteger
rst.Fields.Append "xx2", adChar, 5
rst.Open

For Each ofld In rst.Fields
    Debug.Print ofld.Name
Next 

2. Use the Shape Provider Service to append the additional Fields on at the time the recordset is open. This sample uses the Biblio.mdb:




Dim rst As New ADODB.Recordset

rst.Open "SHAPE {SELECT author FROM authors}" & _
         "APPEND NEW adChar(10) NewCol1, NEW adChar(10) NewCol2", _
         "Provider=MSDATASHAPE" & _
         ";Data Provider=MSDASQL" & _
         ";Data Source=<your_dsn>" & _
         ";User ID=;Password=;", _
         adOpenStatic, adLockBatchOptimistic

For Each ofld In rst.Fields
   Debug.Print ofld.Name
Next

rst.AddNew Array("author", "NewCol1", "NewCol2"), _
           Array("Detroit", "string1", "string2")

rst.MoveFirst
   While rst.EOF <> True
   Debug.Print rst!author, rst!NewCol1, rst!NewCol2
   rst.MoveNext
Wend 

STATUS

This behavior is by design.

MORE INFORMATION

Steps to Reproduce Behavior

1. Start Visual Basic and select a New Standard EXE Project. Form1 is created by default.



2. Add the following Project Reference:


Microsoft ActiveX Data Objects Library


3. Pass the following code in the Load Method of the default Form. This sample uses the Biblio.mdb:




Dim rst As New ADODB.Recordset
    
rst.Open "SELECT * FROM authors", _
         "Provider=MSDASQL;Data Source=<your_dsn>;User ID=;Password=;", _
          adOpenStatic, adLockBatchOptimistic
          
rst.Fields.Append "xx1", adInteger 

4. Run the project.

© Microsoft Corporation 1999, All Rights Reserved.
Contributions by Matthew Hofacker, Microsoft Corporation

Additional query words: column

Keywords : kberrmsg kbADO200 kbADO201 kbADO210 kbDatabase kbGrpVBDB
Version : WINDOWS:2.0,2.01,2.1
Platform : WINDOWS
Issue type : kbprb