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ms-accessvbavb5

How can I use the database commands 'Seek' and results 'NoMatch'?


Here's my problem:

Let's say I have these tables:

table1

1 - "a"

2 - "b"

table2

1 -

2 -

3 -

Now, I'm using the following code to compare the tables:

table2.MoveFirst
Do While Not table2.EOF
 table1.Seek "=", table2!field2
  If table1.NoMatch Then
               go do a lot of things to find that information
  Else 
   table2.Edit
   table2!Field2 = table1!field2
   table2.update
  End If
 table2.MoveNext
Loop

But the line

table2!Field2 = table1!field2

Is not working so well. I'm pretty sure I'm doing something wrong here, but I'm having problems finding a solution. I'm not even sure what I should google...

EDIT: Field 2 is indexed in table 1, so the 'seek' works.


Solution

  • A few notes.

    Let us say you want all the records from Table2 where there is no match on a field called Field1:

    sSQL = "SELECT Field1, FieldX FROM Table2 " _
         & "LEFT JOIN Table1 " _
         & "ON Table2.Field1 = Table1.Field1 " _
         & "WHERE Table1.Field1 Is Null"
    

    You could, of course, build the query in the query design window and fiddle around until is is just what you want, then switch to SQL view to get the right (ish) SQL string.

    Dim rs As DAO.Recordset
    
    Set rs = CurrentDB.Openrecordset(sSQL)
    
    ''table2.MoveFirst
    Do While Not rs.EOF ''table2.EOF
    
    ''You do not need no match, all these records are missing a match
    ''    table1.Seek "=", table2!field2
    ''    If table1.NoMatch Then
               go do a lot of things to find that information
        rs.MoveNext
    Loop
    ''This can all be done with one update query
    ''    Else 
    ''    table2.Edit
    ''    table2!Field2 = table1!field2
    ''    table2.update
    ''    End If
    ''    table2.MoveNext
    ''    Loop
    
    sSQL = "UPDATE Table2 " _
         & "INNER JOIN Table1 " _
         & "SET table2.Field2 = table1.field2 " 
    
    CurrentDB.Execute sSQL dbFailOnerror
    

    Please treat the above as notes, not finished code.