PostgreSQL/Inheritance/Update Inheritance Only — различия между версиями

Материал из SQL эксперт
Перейти к: навигация, поиск
м (1 версия)
 
м (1 версия)
 
(нет различий)

Текущая версия на 10:14, 26 мая 2010

Modifying parent tables with ONLY

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=# -- Modifying parent tables with ONLY
postgres=#
postgres=# UPDATE only authors SET first_name = "Paul"
postgres-#                 WHERE last_name = "Simon";
UPDATE 0
postgres=#
postgres=# SELECT * FROM distinguished_authors;
 id | last_name | first_name | award
----+-----------+------------+-------
  1 | S         | N          | Prize
(1 row)
postgres=#
postgres=# SELECT * FROM authors;
 id | last_name | first_name
----+-----------+------------
  1 | S         | N
(1 row)
postgres=#
postgres=# drop table distinguished_authors;
DROP TABLE
postgres=# drop table authors;
DROP TABLE
postgres=#