Pfthb

I am encountering a strange bug when I try to swap values between two recordsets. The source of the problem appears to come from the fact that the field I am swapping is also the field that I query from initially.
Here are the logical steps to understand it more clearly:

1. Store all the records where PhaseID is equal to X into Recordset A


2. Store all the records where PhaseID is equal to Y into Recordset B


3. Set all records in Recordset A to have PhaseID equal to Y


4. Set all records in Recordset B to have PhaseID equal to X

Here is my actual code:

Private Sub swapReferences(firstRec() As Variant, secondRec() As Variant)
 ...
 Set rstFirst = CurrentDb.OpenRecordset("Select * From Scenarios Where PhaseID = " & firstRec(0))
 Set rstSecond = CurrentDb.OpenRecordset("Select * From Scenarios Where PhaseID = " & secondRec(0))

 updateRecords rstFirst, "PhaseID", secondRec(0)
 updateRecords rstSecond, "PhaseID", firstRec(0)
End Sub

Private Sub updateRecords(rst As Recordset, fieldName As String, newVal As Variant)
 While Not rst.EOF
 rst.Edit
 rst(fieldName) = newVal
 rst.update
 rst.MoveNext
 Wend
End Sub

The strange thing is that this code may work the first time (in that the values are actually swapped). But the second time, it is almost guaranteed to fail. What happens is that instead of the rows being swapped, one of the recordsets gets all of the records and the other gets none. It is as if rstSecond gets dynamically larger when rstFirst updates its records to have the values that rstSecond had queried with.

What is even stranger is that I seemed to have found a fix that does not make any sense. I modified the first function as shown:

Private Sub swapReferences(firstRec() As Variant, secondRec() As Variant)
 Set rstFirst = CurrentDb.OpenRecordset("Select * From Scenarios Where PhaseID = " & firstRec(0))
 Set rstSecond = CurrentDb.OpenRecordset("Select * From Scenarios Where PhaseID = " & secondRec(0))

 'Debug
 If Not rstSecond.EOF Then
 'For whatever reason .RecordCount isn't accurate unless the last record has been accessed
 rstSecond.MoveLast
 Debug.Print rstSecond.RecordCount
 rstSecond.MoveFirst
 End If

 updateRecords rstFirst, "PhaseID", secondRec(0)

 'Debug
 If Not rstSecond.EOF Then
 rstSecond.MoveLast
 Debug.Print rstSecond.RecordCount
 rstSecond.MoveFirst
 End If

 updateRecords rstSecond, "PhaseID", firstRec(0)
End Sub

Those if blocks were used to see if rstSecond was magically changing its size after rstFirst updated its records. When I ran the code with these debug blocks, I discovered that not only was rstSecond remaining constant but my code worked as intended.

So my question is two-fold: why did adding those debug blocks fix my code? And is there a more appropriate way to do what I want to do so my code does not appear to be so nonsensical?