ACC: RecordsAffected Property Incorrect for SQL Pass-Through

• Microsoft Access versions 7.0, 97

SYMPTOMS

Moderate: Requires basic macro, coding, and interoperability skills.

When you use the RecordsAffected property of a Database or QueryDef object to determine the number of records affected by the Execute method, the value is incorrect with SQL pass-through queries.

This article assumes that you are familiar with Visual Basic for Applications and with creating Microsoft Access applications using the programming tools provided with Microsoft Access. For more information about Visual Basic for Applications, please refer to your version of the "Building Applications with Microsoft Access" manual.

CAUSE

The RecordsAffected property is not set when you execute a pass-through query.

STATUS

This behavior is by design.

MORE INFORMATION

When you view the RecordsAffected property, it reflects the number of records affected by the most recent Execute method on an object that uses the Microsoft Jet database engine. Pass-through queries bypass the Jet database engine and interact directly with the back-end database through the ODBC driver.

The following example shows a correct RecordsAffected value because the Execute method operates on a table in the sample database Northwind.mdb:

1. Start Microsoft Access and open the sample database Northwind.mdb.



2. Create a module and type the following procedure:




      Sub ViewRecs()
         Dim db As DATABASE
         ' Substitute the correct path to Northwind.mdb on your computer.
         Set db = DBEngine.Workspaces(0).OpenDatabase _
         ("C:\Program Files\Microsoft Office\Office\Samples\Northwind.mdb")
         db.Execute "Update employees set country = 'United States' " _
          & "where country = 'USA';"
         Msgbox db.RecordsAffected
      End Sub 

3. To test this procedure, type the following line in the Debug window, and then press ENTER:

   
   ViewRecs 

   Note that a message box opens and displays the number of records affected by the update. The number is 5 in an unaltered copy of Northwind.mdb.

Steps to Reproduce Behavior

1. Start Microsoft Access and open the sample database Northwind.mdb.



2. Create a module and type the following procedure:




      Sub WrongNum()
         Dim db As DATABASE
         Dim SPTErr As Error
         On Error GoTo WrongNum_err
         ' Substitute your own ODBC connection parameters.
         Set db = OpenDatabase("", False, False, _
            "ODBC;DSN=Pubs1;DATABASE=pubs;UID=sa;PWD=")
         ' Create a table in SQL Server and create a unique index.
         db.Execute "create table testrecs (f1 int)", dbSQLPassThrough
         db.Execute "create unique index idx on testrecs (f1)", _
            dbSQLPassThrough

         ' Insert two records.
         db.Execute "Insert into testrecs values(1)", dbSQLPassThrough
         db.Execute "Insert into testrecs values(2)", dbSQLPassThrough

         ' This message box returns 0 records.
         Msgbox db.RecordsAffected & " Records Affected."

         ' Delete the testrecs table.
         db.Execute "drop table testrecs", dbSQLPassThrough

         ' This message box returns 0 records.
         Msgbox db.RecordsAffected & " Records Affected."
       Exit Sub
         WrongNum_err:
         For Each SPTErr In DBEngine.Errors
            With SPTErr
               Msgbox .Number & vbcr & .Description & vbcr & .Source
            End With
         Next SPTErr
      End Sub 

3. To test this procedure, type the following line in the Debug window, and then press ENTER.

   WrongNum

   Note that a message box opens twice and displays the number 0 instead of the actual number of records affected, which is 2.

REFERENCES

For more information about the RecordsAffected property, search the Help Index for "RecordsAffected property."

Additional query words:

Keywords : kbusage AccCon MdlQry QryPass
Version : WINDOWS:7.0,97
Platform : WINDOWS
Issue type : kbprb