From: Michael_Schutte@xxxxxxxxxxxx

You are right Joe...

I went the route of union because I assumed Ash wanted records from both
tables. From what I can see, if you join the two tables, you will miss
the records that are unique in the joined table.

So if table 1 has 1 record and table 2 has 3. And you join table 2 to
table 1, your result will only be 1 record.

Absolutely right, Michael. Yet another reason why programming is less about
the language and more about succinctly defining the business problem! If
there are records in T2 that are not overriding records in T1, then those
records will not be included in a LEFT OUTER JOIN (that's the underlying
feature of a JOIN: the primary file drives the data selection).

My assumption is that all id/type combinations in T2 are also in T1, your
assumption is that they may not be. The technique chosen will probably rely
on the data (although if the answer is not known, your solution gets the nod
because it handles both cases).


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