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

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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.

3

There are 3 best solutions below

2
On BEST ANSWER

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.

1
On

But the line table2!Field2 = table1!field2 Is not working so well

...is not a good description of what goes wrong.

Does the code stop/crash at this line?
Does it run without errors, but do nothing / something else than you expected?

I suppose that you're using DAO Recordsets.
It's hard to give advice without more information, but I'll give it a try:

  1. Is table2 completely empty? Your description looks like this:

    table2
    1 -
    2 -
    3 -

    If yes, the whole loop is probably never executed at all.

  2. Can the Recordset table2 be updated?
    Not all types of Recordsets support this, it depends on how you create it. See MSDN: Recordset Object (DAO), there is a list of Recordset types at the beginning.
    If it's not updateable, you should get an error when you call .Update.

0
On

If you're using DAO recordsets (as suggested by Christian) you can change the line

table2!Field2 = table1!field2

to

table2.Fields("Field2").value = table1.Fields("field2").value

I'm presuming both Field2's are of Text data type.