MS Access- order of occurrence - ms-access

Question

I am struggling with the following thing in MS Access: I want to assign each record an nth order of its occurrence (1st, 2nd time NOT TOTAL number of occurrences).
Comparing to Excel, it should work like countif with moving range. For example, if the values are stored in column B that would be
=countif($B$1:B1,B1)

Answer 1

You can use my RowCounter function.
Please study the in-line comments for typical usage:
Public Function RowCounter( _
ByVal strKey As String, _
ByVal booReset As Boolean, _
Optional ByVal strGroupKey As String) _
As Long
' Builds consecutive RowIDs in select, append or create query
' with the possibility of automatic reset.
' Optionally a grouping key can be passed to reset the row count
' for every group key.
'
' Usage (typical select query):
' SELECT RowCounter(CStr([ID]),False) AS RowID, *
' FROM tblSomeTable
' WHERE (RowCounter(CStr([ID]),False) <> RowCounter("",True));
'
' Usage (with group key):
' SELECT RowCounter(CStr([ID]),False,CStr[GroupID])) AS RowID, *
' FROM tblSomeTable
' WHERE (RowCounter(CStr([ID]),False) <> RowCounter("",True));
'
' The Where statement resets the counter when the query is run
' and is needed for browsing a select query.
'
' Usage (typical append query, manual reset):
' 1. Reset counter manually:
' Call RowCounter(vbNullString, False)
' 2. Run query:
' INSERT INTO tblTemp ( RowID )
' SELECT RowCounter(CStr([ID]),False) AS RowID, *
' FROM tblSomeTable;
'
' Usage (typical append query, automatic reset):
' INSERT INTO tblTemp ( RowID )
' SELECT RowCounter(CStr([ID]),False) AS RowID, *
' FROM tblSomeTable
' WHERE (RowCounter("",True)=0);
'
' 2002-04-13. Cactus Data ApS. CPH
' 2002-09-09. Str() sometimes fails. Replaced with CStr().
' 2005-10-21. Str(col.Count + 1) reduced to col.Count + 1.
' 2008-02-27. Optional group parameter added.
' 2010-08-04. Corrected that group key missed first row in group.
Static col As New Collection
Static strGroup As String
On Error GoTo Err_RowCounter
If booReset = True Then
Set col = Nothing
ElseIf strGroup <> strGroupKey Then
Set col = Nothing
strGroup = strGroupKey
col.Add 1, strKey
Else
col.Add col.Count + 1, strKey
End If
RowCounter = col(strKey)
Exit_RowCounter:
Exit Function
Err_RowCounter:
Select Case Err
Case 457
' Key is present.
Resume Next
Case Else
' Some other error.
Resume Exit_RowCounter
End Select
End Function

Answer 2

Consider a correlated count subquery or conditional DCount for SELECT statements. Below assumes you have an autonumber field, ID, in myTable:
SELECT t.[value], (SELECT Count(*) FROM myTable
WHERE sub.[value] = t.[value]
AND sub.ID <= t.ID) As value_rank
FROM myTable t
SELECT t.[value],
DCount("*", "myTable",
"[value] = " & t.[value] & " AND ID <= " & t.ID) As value_rank
FROM myTable t
For UPDATE queries, you would need the DCount for it to be an updateable query:
UPDATE myTable t
SET t.value = DCount("*", "myTable",
"[value] = " & t.value & " AND ID <= " & t.ID)
If value is a string, wrap concatenation with single quotes: ... "[value] = '" & t.value & "' ... If value is a date, wrap with hashtags: ... "[value] = #" & t.value & "# ...