No hay FULL OUTER JOIN en MySQL. Consulte 7.2.12. Simplificación de combinación externa
y 12.2.8.1. Sintaxis JOIN
:
Puede emular FULL OUTER JOIN usando UNION (desde MySQL 4.0.0 en adelante):
con dos tablas t1, t2:
SELECT * FROM t1
LEFT JOIN t2 ON t1.id = t2.id
UNION
SELECT * FROM t1
RIGHT JOIN t2 ON t1.id = t2.id
con tres tablas t1, t2, t3:
SELECT * FROM t1
LEFT JOIN t2 ON t1.id = t2.id
LEFT JOIN t3 ON t2.id = t3.id
UNION
SELECT * FROM t1
RIGHT JOIN t2 ON t1.id = t2.id
LEFT JOIN t3 ON t2.id = t3.id
UNION
SELECT * FROM t1
RIGHT JOIN t2 ON t1.id = t2.id
RIGHT JOIN t3 ON t2.id = t3.id
