I found this explanation of FULL OUTER JOINS syntax on: https://hightouch.com/sql-dictionary/sql-full-join
The syntax for a SQL FULL JOIN operation is as follows: SELECT column_list FROM table1 FULL JOIN table2 ON table1.column = table2.column; * column_list: A list of columns to retrieve from the joined tables. * table1 and table2: The names of the tables to be joined. * column: The common column or key that relates the tables. I implemented it on my code as: MATCH FILES SELECT CountyCode VoterID LastName FirstName MiddleName ResidenceAddress1 ResidenceAddress2 ResidenceAddressCity ResidenceState Gender Race BirthDate RegistrationDate Party20241112 VoterStatus DaytimeAreaCode DaytimePhonenumber Emailadress Party_20241022 FROM /FILE = "F:\External Drive for PSPP Data\FloridaTotalsFiles\SelectedFields_20241112.sav" FULL OUTER JOIN /FILE = "F:\External Drive for PSPP Data\FloridaTotalsFiles\VoterIDParty_20241022.sav" /BY VoterID. And this is its Output MATCH FILES Untitled.sps:2.1: error: MATCH FILES: Syntax error expecting FILE or TABLE. 2 | SELECT CountyCode VoterID LastName FirstName MiddleName ResidenceAddress1 ResidenceAddress2 ResidenceAddressCity ResidenceState Gender Race BirthDate RegistrationDate Party20241112 VoterStatus DaytimeAreaCode DaytimePhonenumber Emailadress Party_20241022 | ^ Untitled.sps:2.1-2.6: error: SELECTPRED: SELECTPRED is not yet implemented. 2 | SELECT CountyCode VoterID LastName FirstName MiddleName ResidenceAddress1 ResidenceAddress2 ResidenceAddressCity ResidenceState Gender Race BirthDate RegistrationDate Party20241112 VoterStatus DaytimeAreaCode DaytimePhonenumber Emailadress Party_20241022 | ^~~~~~ SELECT CountyCode VoterID LastName FirstName MiddleName ResidenceAddress1 ResidenceAddress2 ResidenceAddressCity ResidenceState Gender Race BirthDate RegistrationDate Party20241112 VoterStatus DaytimeAreaCode DaytimePhonenumber Emailadress Party_20241022 Untitled.sps:4.1-4.4: error: Unknown command `FROM'. 4 | FROM /FILE = "F:\External Drive for PSPP Data\FloridaTotalsFiles\SelectedFields_20241112.sav" | ^~~~ FROM /FILE = "F:\External Drive for PSPP Data\FloridaTotalsFiles\SelectedFields_20241112.sav" FULL OUTER JOIN /FILE = "F:\External Drive for PSPP Data\FloridaTotalsFiles\VoterIDParty_20241022.sav" /BY VoterID. Is this not working because it has not yet been implemented? Or do I need to make some changes to my implementation for it to work?