PostgreSQL/Inheritance/Children Table — различия между версиями
Admin (обсуждение | вклад) м (1 версия) |
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(нет различий)
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Текущая версия на 13:14, 26 мая 2010
Creating a child table
<source lang="sql">
postgres=# postgres=# postgres=# -- Creating a child table postgres=# postgres=# CREATE TABLE "authors" ( postgres(# "id" integer NOT NULL, postgres(# "last_name" text, postgres(# "first_name" text, postgres(# Constraint "authors_pkey" Primary Key ("id") postgres(# ); NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "authors_pkey" for table "authors" CREATE TABLE postgres=# postgres=# postgres=# CREATE TABLE distinguished_authors (award text) postgres-# INHERITS (authors); CREATE TABLE postgres=# postgres=# INSERT INTO distinguished_authors postgres-# VALUES (1,"S", "N", "Prize"); INSERT 0 1 postgres=# postgres=# -- Selecting with inheritance postgres=# postgres=# SELECT * FROM distinguished_authors postgres-# WHERE last_name = "S";
id | last_name | first_name | award
+-----------+------------+-------
1 | S | N | Prize
(1 row) postgres=# postgres=# postgres=# drop table distinguished_authors; DROP TABLE postgres=# drop table authors; DROP TABLE postgres=#
</source>