Changes

Even if you manually checked the excel sheet for Warning Multiple Matches with the Hall warning, there still may be duplicates. Check this To get rid of these specify that a query where you join a table of only singular primary keys to the original table. That way you will have unique primary keys by running:construction.

SELECT COUNT(*) FROM(SELECT targetname, targetstate, announceddate FROM MAClean)a; --7206  SELECT COUNT(*) FROM(SELECT DISTINCT targetname, targetstate, announceddate FROM MAClean)a; --7189  SELECT COUNT(*) FROM(SELECT issuername, issuerstate, issuedate FROM IPOClean)a; --2146  SELECT COUNT(*) FROM(SELECT DISTINCT issuername, issuerstate, issuedate FROM IPOClean)a; --2141  As you can see, I still have duplicates in both the MAClean and IPOClean files. I ran an aggregate function to get rid of these duplicates: There are two companies that have the name Masspower in the MACleanNoDups MAClean file. One is written in all caps and will thus not be caught by the an aggregate function. I will select only the companies where the primary keys occurs once and join this to MAClean. I will then select needed info from MANoDps.