merging records from querying two tables is it possible
I have two sets of invoice information one before a certain date, the other after that date. I want to keep them separate so that the older set of data is only used for a specific query which is run only occasionally. I do not want to merge the tables. Each set of invoice information is in two tables, one contains info of the invoice, the other a table of the line items in the invoice.
Is it possible to run a query, say find me all the invoices where x item was sold, so that the results are pulled from both the newer and older sets of data?