в 13:45, 26 мая 2010

2010-05-26T13:45:56Z

Admin: 1 версия

2010-05-26T10:14:35Z

1 версия

Новая страница

==An array may also be updated at a single element==



<source lang="sql">

postgres=#
postgres=#
postgres=# CREATE TABLE sal_emp (
postgres(# name text,
postgres(# pay_by_quarter integer[],
postgres(# schedule text[][]
postgres(# );
CREATE TABLE
postgres=#
postgres=# INSERT INTO sal_emp
postgres-# VALUES ("Bill",
postgres(# ARRAY[10000, 10000, 10000, 10000],
postgres(# ARRAY[["meeting", "lunch"], ["training", "presentation"]]);
INSERT 0 1
postgres=#
postgres=# INSERT INTO sal_emp
postgres-# VALUES ("Carol",
postgres(# ARRAY[20000, 25000, 25000, 25000],
postgres(# ARRAY[["breakfast", "consulting"], ["meeting", "lunch"]]);
INSERT 0 1
postgres=#
postgres=# SELECT * FROM sal_emp;
name | pay_by_quarter | schedule
-------+---------------------------+-------------------------------------------
Bill | {10000,10000,10000,10000} | {{meeting,lunch},{training,presentation}}
Carol | {20000,25000,25000,25000} | {{breakfast,consulting},{meeting,lunch}}
(2 rows)
postgres=#
postgres=#
postgres=# -- An array may also be updated at a single element:
postgres=#
postgres=# UPDATE sal_emp SET pay_by_quarter[4] = 15000 WHERE name = "Bill";
UPDATE 1
postgres=#
postgres=# select * from sal_emp;
name | pay_by_quarter | schedule
-------+---------------------------+-------------------------------------------
Carol | {20000,25000,25000,25000} | {{breakfast,consulting},{meeting,lunch}}
Bill | {10000,10000,10000,15000} | {{meeting,lunch},{training,presentation}}
(2 rows)
postgres=#
postgres=# drop table sal_emp;
DROP TABLE
postgres=#
postgres=#

</source>

==An array value can be replaced completely==



<source lang="sql">

postgres=#
postgres=#
postgres=# CREATE TABLE sal_emp (
postgres(# name text,
postgres(# pay_by_quarter integer[],
postgres(# schedule text[][]
postgres(# );
CREATE TABLE
postgres=#
postgres=# INSERT INTO sal_emp
postgres-# VALUES ("Bill",
postgres(# ARRAY[10000, 10000, 10000, 10000],
postgres(# ARRAY[["meeting", "lunch"], ["training", "presentation"]]);
INSERT 0 1
postgres=#
postgres=# INSERT INTO sal_emp
postgres-# VALUES ("Carol",
postgres(# ARRAY[20000, 25000, 25000, 25000],
postgres(# ARRAY[["breakfast", "consulting"], ["meeting", "lunch"]]);
INSERT 0 1
postgres=#
postgres=# SELECT * FROM sal_emp;
name | pay_by_quarter | schedule
-------+---------------------------+-------------------------------------------
Bill | {10000,10000,10000,10000} | {{meeting,lunch},{training,presentation}}
Carol | {20000,25000,25000,25000} | {{breakfast,consulting},{meeting,lunch}}
(2 rows)
postgres=#
postgres=# -- An array value can be replaced completely:
postgres=#
postgres=# UPDATE sal_emp SET pay_by_quarter = "{25000,25000,27000,27000}" WHERE name = "Carol";
UPDATE 1
postgres=#
postgres=# SELECT * FROM sal_emp;
name | pay_by_quarter | schedule
-------+---------------------------+-------------------------------------------
Bill | {10000,10000,10000,10000} | {{meeting,lunch},{training,presentation}}
Carol | {25000,25000,27000,27000} | {{breakfast,consulting},{meeting,lunch}}
(2 rows)
postgres=#
postgres=# drop table sal_emp;
DROP TABLE
postgres=#
postgres=#

</source>

==Modifying an array subscript==



<source lang="sql">

postgres=#
postgres=# CREATE TABLE book (id integer,titles text[]);
CREATE TABLE
postgres=#
postgres=# INSERT INTO book VALUES (102, "{"AAA\"s VVVV"}");
INSERT 0 1
postgres=# INSERT INTO book VALUES (103, "{"AAA", "VVVV"}");
INSERT 0 1
postgres=#
postgres=# -- Modifying an array subscript
postgres=#
postgres=#
postgres=# UPDATE book
postgres-# SET titles[1] = "New\"s New"
postgres-# WHERE titles[1] = "AAA";
UPDATE 1
postgres=#
postgres=# SELECT titles[1] FROM book;
titles
------------
AAA"s VVVV
New"s New
(2 rows)
postgres=#
postgres=# drop table book;
DROP TABLE
postgres=#
postgres=#

</source>

==Update array value==



<source lang="sql">

postgres=# CREATE TABLE book (id integer,titles text[]);
CREATE TABLE
postgres=#
postgres=# INSERT INTO book VALUES (102, "{"AAA\"s VVVV"}");
INSERT 0 1
postgres=# INSERT INTO book VALUES (103, "{"AAA", "VVVV"}");
INSERT 0 1
postgres=#
postgres=# select * from book;
id | titles
-----+----------------
102 | {"AAA"s VVVV"}
103 | {AAA,VVVV}
(2 rows)
postgres=#
postgres=# UPDATE book
postgres-# SET titles="{"AAA\"s VVV","ABC"}"
postgres-# WHERE id = 102;
UPDATE 1
postgres=#
postgres=# select * from book;
id | titles
-----+-------------------
103 | {AAA,VVVV}
102 | {"AAA"s VVV",ABC}
(2 rows)
postgres=#
postgres=# drop table book;
DROP TABLE
postgres=#
postgres=#

</source>

==Update in a slice==



<source lang="sql">

postgres=#
postgres=#
postgres=# CREATE TABLE sal_emp (
postgres(# name text,
postgres(# pay_by_quarter integer[],
postgres(# schedule text[][]
postgres(# );
CREATE TABLE
postgres=#
postgres=# INSERT INTO sal_emp
postgres-# VALUES ("Bill",
postgres(# ARRAY[10000, 10000, 10000, 10000],
postgres(# ARRAY[["meeting", "lunch"], ["training", "presentation"]]);
INSERT 0 1
postgres=#
postgres=# INSERT INTO sal_emp
postgres-# VALUES ("Carol",
postgres(# ARRAY[20000, 25000, 25000, 25000],
postgres(# ARRAY[["breakfast", "consulting"], ["meeting", "lunch"]]);
INSERT 0 1
postgres=#
postgres=# SELECT * FROM sal_emp;
name | pay_by_quarter | schedule
-------+---------------------------+-------------------------------------------
Bill | {10000,10000,10000,10000} | {{meeting,lunch},{training,presentation}}
Carol | {20000,25000,25000,25000} | {{breakfast,consulting},{meeting,lunch}}
(2 rows)
postgres=#
postgres=# -- Update in a slice:
postgres=#
postgres=# UPDATE sal_emp SET pay_by_quarter[1:2] = "{27000,27000}" WHERE name = "Carol";
UPDATE 1
postgres=#
postgres=# select * from sal_emp;
name | pay_by_quarter | schedule
-------+---------------------------+-------------------------------------------
Bill | {10000,10000,10000,10000} | {{meeting,lunch},{training,presentation}}
Carol | {27000,27000,25000,25000} | {{breakfast,consulting},{meeting,lunch}}
(2 rows)
postgres=#
postgres=# drop table sal_emp;
DROP TABLE
postgres=#

</source>

==Using the ARRAY expression syntax==



<source lang="sql">
postgres=#
postgres=#
postgres=#
postgres=# CREATE TABLE sal_emp (
postgres(# name text,
postgres(# pay_by_quarter integer[],
postgres(# schedule text[][]
postgres(# );
CREATE TABLE
postgres=#
postgres=# INSERT INTO sal_emp
postgres-# VALUES ("Bill",
postgres(# ARRAY[10000, 10000, 10000, 10000],
postgres(# ARRAY[["meeting", "lunch"], ["training", "presentation"]]);
INSERT 0 1
postgres=#
postgres=# INSERT INTO sal_emp
postgres-# VALUES ("Carol",
postgres(# ARRAY[20000, 25000, 25000, 25000],
postgres(# ARRAY[["breakfast", "consulting"], ["meeting", "lunch"]]);
INSERT 0 1
postgres=#
postgres=# SELECT * FROM sal_emp;
name | pay_by_quarter | schedule
-------+---------------------------+-------------------------------------------
Bill | {10000,10000,10000,10000} | {{meeting,lunch},{training,presentation}}
Carol | {20000,25000,25000,25000} | {{breakfast,consulting},{meeting,lunch}}
(2 rows)
postgres=#
postgres=# -- using the ARRAY expression syntax:
postgres=#
postgres=# UPDATE sal_emp SET pay_by_quarter = ARRAY[25000,25000,27000,27000] WHERE name = "Carol";
UPDATE 1
postgres=#
postgres=# select * from sal_emp;
name | pay_by_quarter | schedule
-------+---------------------------+-------------------------------------------
Bill | {10000,10000,10000,10000} | {{meeting,lunch},{training,presentation}}
Carol | {25000,25000,27000,27000} | {{breakfast,consulting},{meeting,lunch}}
(2 rows)
postgres=#
postgres=# drop table sal_emp;
DROP TABLE
postgres=#
postgres=#
postgres=#

</source>

← Предыдущая	Версия 13:45, 26 мая 2010
(нет различий)

PostgreSQL/Array/Array Column Update - История изменений

в 13:45, 26 мая 2010

Admin: 1 версия