I have a form/update page that works fine when I put data in the fields.
If there is data in the field already (and displayed in the form), then setting that field to null (taking the data out), has no effect.
Other changes to fields on that form happen but not these null fields.
Is this a known feature, or I am doing something wrong ?
Here's the relevant code:

.... validation code...

.... connect to Access database....

' 'Build the update string
strSQL = "Update Publications Set "
strSQL = strSQL & "[Publication Type] = '" & Request.Form("txtType") & "', "
strSQL = strSQL & "[Publication Title] = '" & Request.Form("txtTitle") & "', "


strSQL = strSQL & "[Publication County] = '" & Request.Form("txtCounty") & "', "



strSQL = strSQL & "[Publication Author] = '" & Request.Form("txtAuthor") & "', "



strSQL = strSQL & "[Publication Weight] = " & CLng(Request.Form("txtWeight")) & ", "
strSQL = strSQL & "[Publication Price] = " & CCur(Request.Form("txtPrice")) & ", "


strSQL = strSQL & "[Publication Notes] = '" & CStr(Request.Form("Notes2")) & "', "


strSQL = strSQL & "[Publication In Stock] = '" & CStr(Request.Form("txtInStock")) & "' "
strSQL = strSQL & " WHERE [Publication Id] = " & CLng(Request.Form("txtId")) & ";"

response.write "SQL s/m: " & strSQL

' 'Create the recordset object

'response.write "Step 3:" & strSQL
end if
Set oRSPublications = Server.CreateObject("ADODB.Recordset")
oRSPublications.CursorType = 2


oRSPublications.LockType = 3

'
'response.write "display update form: " & strSQL
'


conn.Execute(strSQL)