Untitled

SELECT 'Criterion 1' AS criteria, firstname, lastname, manager, siteid, COUNT(*) AS record_count
FROM users
GROUP BY firstname, lastname, manager, siteid
HAVING COUNT(*) > 1

UNION ALL

SELECT 'Criterion 2' AS criteria, firstname, lastname, NULL AS manager, siteid, COUNT(*) AS record_count
FROM users
GROUP BY firstname, lastname, siteid
HAVING COUNT(*) > 1

UNION ALL

SELECT 'Criterion 3' AS criteria, lastname, firstname, NULL AS manager, siteid, COUNT(*) AS record_count
FROM users
GROUP BY lastname, firstname, siteid
HAVING COUNT(*) > 1

UNION ALL

SELECT 'Criterion 4' AS criteria, NULL AS firstname, NULL AS lastname, NULL AS manager, siteid, COUNT(*) AS record_count
FROM users
GROUP BY REPLACE(firstname || lastname || siteid, ' ', '')
HAVING COUNT(*) > 1;