Using a relationship to join two tables.

I have two tables that I would like to join and then only show me the differences between the two tables. Basically, the two tables have all the same fields and have a lot of the same data. I get a new dataset each month that updates data for existing records and adds new records. 

Everything I can find points towards using a relationship to make the join. Would the table I intend to be the joined table be the parent table? How would I effectively identify the differences between the two tables and only display the records that are either new or updated? Is this possible in Quick Base? Or, would the most effective way be to join the two tables and MySQL and then upload the resulting dataset into Quick Base?

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Holli Mills
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