Bagaimana menemukan LEFT OUTER JOIN atau RIGHT OUTER JOIN dengan ORACLE JOIN (+)

Tolong jelaskan cara mencari join luar kanan dan kiri yang benar beserta contohnya

Saya akan mencoba menunjukkan perbedaan antara Sintaksis gabungan luar Oracle dan Sintaks ANSI/ISO .

KIRI LUAR GABUNG -

SELECT e.last_name,
  d.department_name
FROM employees e,
  departments d
WHERE e.department_id = d.department_id(+);

SELECT e.last_name,
  d.department_name
FROM employees e
LEFT OUTER JOIN departments d
ON (e.department_id = d.department_id);

GABUNG LUAR KANAN -

SELECT e.last_name,
  d.department_name
FROM employees e,
  departments d
WHERE e.department_id(+) = d.department_id;

SELECT e.last_name,
  d.department_name
FROM employees e
RIGHT OUTER JOIN departments d
ON (e.department_id = d.department_id);

GABUNG LUAR PENUH -

Sebelum dukungan asli hash full outerjoin di 11gR1, Oracle akan secara internal mengonversi FULL OUTER JOIN dengan cara berikut -

SELECT e.last_name,
  d.department_name
FROM employees e,
  departments d
WHERE e.department_id = d.department_id(+)
UNION ALL
SELECT NULL,
  d.department_name
FROM departments d
WHERE NOT EXISTS
  (SELECT 1 FROM employees e WHERE e.department_id = d.department_id
  );

SELECT e.last_name,
  d.department_name
FROM employees e
FULL OUTER JOIN departments d
ON (e.department_id = d.department_id);

Lihat ini.