You cannot run the script without category, the SQL fails - we should either fix this or note that category is mandatory in the script

root@kohadevbox:koha(master)$ perl misc/cronjobs/delete_patrons.pl --expired_before =1910-01-01
C4::Members::GetBorrowersToExpunge(): DBI Exception: DBD::mysql::st execute failed: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ')  GROUP BY borrowers.borrowernumber
        ) xxx WHERE currentissue IS NULL' at line 12 [for Statement "
        SELECT *
        FROM (
            SELECT borrowers.borrowernumber,
                   MAX(old_issues.timestamp) AS latestissue,
                   MAX(issues.timestamp) AS currentissue
            FROM   borrowers
            JOIN   categories USING (categorycode)
            LEFT JOIN (
                SELECT guarantor_id
                FROM borrower_relationships
                WHERE guarantor_id IS NOT NULL
                    AND guarantor_id <> 0
            ) as tmp ON borrowers.borrowernumber=tmp.guarantor_id
            LEFT JOIN old_issues USING (borrowernumber)
            LEFT JOIN issues USING (borrowernumber) WHERE  category_type <> 'S'
        AND ( borrowers.flags IS NULL OR borrowers.flags = 0 )
        AND tmp.guarantor_id IS NULL
     AND dateexpiry < ?  AND categorycode IN ()  GROUP BY borrowers.borrowernumber