Fix upgrade query with Wordpress integration

qa-include/db/install.php

@@ -1587,6 +1587,7 @@ function qa_db_upgrade_tables()
 
 			case 67:
 				// ensure we don't have old userids lying around
+				if (!QA_FINAL_EXTERNAL_USERS) {
 					qa_db_upgrade_query('ALTER TABLE ^messages MODIFY fromuserid ' . $definitions['messages']['fromuserid']);
 					qa_db_upgrade_query('ALTER TABLE ^messages MODIFY touserid ' . $definitions['messages']['touserid']);
 					qa_db_upgrade_query('UPDATE ^messages SET fromuserid=NULL WHERE fromuserid NOT IN (SELECT userid FROM ^users)');
@@ -1594,6 +1595,7 @@ function qa_db_upgrade_tables()
 					// set up foreign key on messages table
 					qa_db_upgrade_query('ALTER TABLE ^messages ADD CONSTRAINT ^messages_ibfk_1 FOREIGN KEY (fromuserid) REFERENCES ^users(userid) ON DELETE SET NULL');
 					qa_db_upgrade_query('ALTER TABLE ^messages ADD CONSTRAINT ^messages_ibfk_2 FOREIGN KEY (touserid) REFERENCES ^users(userid) ON DELETE SET NULL');
+				}
 
 				qa_db_upgrade_query($locktablesquery);
 				break;