comparing two tables

how can i get a query or specific output dependent on data from two fields on one table to match data from two fields on a different table.
if a and b from table one match to c and d from table two, then some specific event happens, like a message stating success or the form turns yellow or something?

Bit of a funny one but you could try a (rather inefficent) loop method. I had to do something similar...


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Dim db as Database
dim tab1 as recordset
dim tab2 as recordset
dim results as string

set db = currentdb

Set tab1 = db.openrecordset("table1")
Set tab2 = db.openrecordset("table2")

With tab1
.MoveFirst
Do until .EOF
tab2.movefirst
Do until tab2.EOF
If .Fields("fieldA") = tab2.fields("fieldC") AND .Fields("fieldB") = tab2.fields("fieldD") then
results = results & "Table 1, Record " & .fields("RecID") & " matches Table 2, Record " & tab2.fields("RecID") & vbCr
End if
tab2.moveNext
Loop
.movenext
Loop
End With

msgbox results, vbInformation, "Results"

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