多表關聯
更新時間 2025-02-14 10:21:52
最近更新時間: 2025-02-14 10:21:52
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本文為您介紹SELECT語法中多表關聯的使用方法。
內連接
teledb=# select * from teledb_pg inner join teledb_pg1 on teledb_pg.id = teledb_pg1.id; id | nickname | id | nickname ----+----------+----+---------- 3 | pg | 3 | pg (1 row)左外連接
teledb=# select * from teledb_pg left join teledb_pg1 on teledb_pg.id = teledb_pg1.id; id | nickname | id | nickname ----+------------+----+---------- 1 | teledb | | 1 | hello,pgxc | | 2 | TELEDB | | 3 | pg | 3 | pg 4 | | | (5 rows)右外連接
teledb=# select * from teledb_pg right join teledb_pg1 on teledb_pg.id = teledb_pg1.id; id | nickname | id | nickname ----+----------+----+---------- | | 5 | test 3 | pg | 3 | pg (2 rows)全連接
teledb=# select * from teledb_pg full join teledb_pg1 on teledb_pg.id = teledb_pg1.id; id | nickname | id | nickname ----+------------+----+---------- 1 | teledb | | 3 | pg | 3 | pg 4 | | | 1 | hello,pgxc | | 2 | TELEDB | | | | 5 | test (6 rows)
