в 13:45, 26 мая 2010

2010-05-26T13:45:56Z

Admin: 1 версия

2010-05-26T10:14:27Z

1 версия

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==Order by in ascending order==



<source lang="sql">

postgres=#
postgres=# CREATE TABLE employee (
postgres(# ID int,
postgres(# name varchar(10),
postgres(# salary real,
postgres(# start_date date,
postgres(# city varchar(10),
postgres(# region char(1)
postgres(# );
CREATE TABLE
postgres=#
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (1, "Jason", 40420, "02/01/94", "New York", "W");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (2, "Robert",14420, "01/02/95", "Vancouver","N");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (3, "Celia", 24020, "12/03/96", "Toronto", "W");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (4, "Linda", 40620, "11/04/97", "New York", "N");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (5, "David", 80026, "10/05/98", "Vancouver","W");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (6, "James", 70060, "09/06/99", "Toronto", "N");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (7, "Alison",90620, "08/07/00", "New York", "W");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (8, "Chris", 26020, "07/08/01", "Vancouver","N");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (9, "Mary", 60020, "06/09/02", "Toronto", "W");
INSERT 0 1
postgres=#
postgres=# select * from employee;
id | name | salary | start_date | city | region
----+--------+--------+------------+-----------+--------
1 | Jason | 40420 | 1994-02-01 | New York | W
2 | Robert | 14420 | 1995-01-02 | Vancouver | N
3 | Celia | 24020 | 1996-12-03 | Toronto | W
4 | Linda | 40620 | 1997-11-04 | New York | N
5 | David | 80026 | 1998-10-05 | Vancouver | W
6 | James | 70060 | 1999-09-06 | Toronto | N
7 | Alison | 90620 | 2000-08-07 | New York | W
8 | Chris | 26020 | 2001-07-08 | Vancouver | N
9 | Mary | 60020 | 2002-06-09 | Toronto | W
(9 rows)
postgres=#
postgres=#
postgres=# SELECT DISTINCT ON (substr) name, substr(name, 1, 1), ascii(name)
postgres-# FROM employee
postgres-# ORDER BY substr ASC;
name | substr | ascii
--------+--------+-------
Alison | A | 65
Celia | C | 67
David | D | 68
Jason | J | 74
Linda | L | 76
Mary | M | 77
Robert | R | 82
(7 rows)
postgres=#
postgres=# drop table employee;
DROP TABLE
postgres=#

</source>

==Using DISTINCT and ORDER BY together==



<source lang="sql">

postgres=#
postgres=# CREATE TABLE employee (
postgres(# ID int,
postgres(# name varchar(10),
postgres(# salary real,
postgres(# start_date date,
postgres(# city varchar(10),
postgres(# region char(1)
postgres(# );
CREATE TABLE
postgres=#
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (1, "Jason", 40420, "02/01/94", "New York", "W");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (2, "Robert",14420, "01/02/95", "Vancouver","N");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (3, "Celia", 24020, "12/03/96", "Toronto", "W");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (4, "Linda", 40620, "11/04/97", "New York", "N");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (5, "David", 80026, "10/05/98", "Vancouver","W");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (6, "James", 70060, "09/06/99", "Toronto", "N");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (7, "Alison",90620, "08/07/00", "New York", "W");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (8, "Chris", 26020, "07/08/01", "Vancouver","N");
INSERT 0 1
postgres=# insert into employee (ID, name, salary, start_date, city, region)
postgres-# values (9, "Mary", 60020, "06/09/02", "Toronto", "W");
INSERT 0 1
postgres=#
postgres=# select * from employee;
id | name | salary | start_date | city | region
----+--------+--------+------------+-----------+--------
1 | Jason | 40420 | 1994-02-01 | New York | W
2 | Robert | 14420 | 1995-01-02 | Vancouver | N
3 | Celia | 24020 | 1996-12-03 | Toronto | W
4 | Linda | 40620 | 1997-11-04 | New York | N
5 | David | 80026 | 1998-10-05 | Vancouver | W
6 | James | 70060 | 1999-09-06 | Toronto | N
7 | Alison | 90620 | 2000-08-07 | New York | W
8 | Chris | 26020 | 2001-07-08 | Vancouver | N
9 | Mary | 60020 | 2002-06-09 | Toronto | W
(9 rows)
postgres=#
postgres=# -- Using DISTINCT and ORDER BY together
postgres=#
postgres=# SELECT DISTINCT city
postgres-# FROM employee
postgres-# ORDER BY city;
city
-----------
New York
Toronto
Vancouver
(3 rows)
postgres=#
postgres=# drop table employee;
DROP TABLE
postgres=#
postgres=#

</source>

==Using DISTINCT with ORDER BY==



<source lang="sql">

postgres=#
postgres=# CREATE TABLE "editions" (
postgres(# "isbn" text NOT NULL,
postgres(# "book_id" integer,
postgres(# "edition" integer,
postgres(# "publisher_id" integer,
postgres(# "publication" date,
postgres(# "type" character(1)
postgres(# );
CREATE TABLE
postgres=#
postgres=# insert into editions values("039480001X", 1608, 1, 59, "1957-03-01", "h");
INSERT 0 1
postgres=# insert into editions values("0451160916", 7808, 1, 75, "1981-08-01", "p");
INSERT 0 1
postgres=# insert into editions values("0394800753", 1590, 1, 59, "1949-03-01", "p");
INSERT 0 1
postgres=# insert into editions values("0590445065", 25908, 1, 150, "1987-03-01", "p");
INSERT 0 1
postgres=# insert into editions values("0694003611", 1501, 1, 65, "1947-03-04", "p");
INSERT 0 1
postgres=# insert into editions values("0679803335", 1234, 1, 102, "1922-01-01", "p");
INSERT 0 1
postgres=#
postgres=# select * from editions;
isbn | book_id | edition | publisher_id | publication | type
------------+---------+---------+--------------+-------------+------
039480001X | 1608 | 1 | 59 | 1957-03-01 | h
0451160916 | 7808 | 1 | 75 | 1981-08-01 | p
0394800753 | 1590 | 1 | 59 | 1949-03-01 | p
0590445065 | 25908 | 1 | 150 | 1987-03-01 | p
0694003611 | 1501 | 1 | 65 | 1947-03-04 | p
0679803335 | 1234 | 1 | 102 | 1922-01-01 | p
(6 rows)
postgres=#
postgres=# -- Using DISTINCT with ORDER BY
postgres=#
postgres=# SELECT DISTINCT ON (edition)
postgres-# edition, publication
postgres-# FROM editions
postgres-# ORDER BY edition ASC,
postgres-# publication DESC;
edition | publication
---------+-------------
1 | 1987-03-01
(1 row)
postgres=#
postgres=#
postgres=#
postgres=# drop table editions;
DROP TABLE
postgres=#
postgres=#
postgres=#

</source>

==Using ORDER BY==



<source lang="sql">

postgres=#
postgres=# CREATE TABLE "editions" (
postgres(# "isbn" text NOT NULL,
postgres(# "book_id" integer,
postgres(# "edition" integer,
postgres(# "publisher_id" integer,
postgres(# "publication" date,
postgres(# "type" character(1)
postgres(# );
CREATE TABLE
postgres=#
postgres=# insert into editions values("039480001X", 1608, 1, 59, "1957-03-01", "h");
INSERT 0 1
postgres=# insert into editions values("0451160916", 7808, 1, 75, "1981-08-01", "p");
INSERT 0 1
postgres=# insert into editions values("0394800753", 1590, 1, 59, "1949-03-01", "p");
INSERT 0 1
postgres=# insert into editions values("0590445065", 25908, 1, 150, "1987-03-01", "p");
INSERT 0 1
postgres=# insert into editions values("0694003611", 1501, 1, 65, "1947-03-04", "p");
INSERT 0 1
postgres=# insert into editions values("0596000855", 41473, 2, 113, "2001-03-01", "p");
INSERT 0 1
postgres=#
postgres=# select * from editions;
isbn | book_id | edition | publisher_id | publication | type
------------+---------+---------+--------------+-------------+------
039480001X | 1608 | 1 | 59 | 1957-03-01 | h
0451160916 | 7808 | 1 | 75 | 1981-08-01 | p
0394800753 | 1590 | 1 | 59 | 1949-03-01 | p
0590445065 | 25908 | 1 | 150 | 1987-03-01 | p
0694003611 | 1501 | 1 | 65 | 1947-03-04 | p
0596000855 | 41473 | 2 | 113 | 2001-03-01 | p
(6 rows)
postgres=#
postgres=# --Using ORDER BY
postgres=#
postgres=# SELECT isbn, edition, publication
postgres-# FROM editions
postgres-# ORDER BY publication ASC;
isbn | edition | publication
------------+---------+-------------
0694003611 | 1 | 1947-03-04
0394800753 | 1 | 1949-03-01
039480001X | 1 | 1957-03-01
0451160916 | 1 | 1981-08-01
0590445065 | 1 | 1987-03-01
0596000855 | 2 | 2001-03-01
(6 rows)
postgres=#
postgres=#
postgres=#
postgres=# drop table editions;
DROP TABLE
postgres=#
postgres=#
postgres=#

</source>

==Using ORDER BY with multiple expressions==



<source lang="sql">
postgres=#
postgres=# CREATE TABLE "editions" (
postgres(# "isbn" text NOT NULL,
postgres(# "book_id" integer,
postgres(# "edition" integer,
postgres(# "publisher_id" integer,
postgres(# "publication" date,
postgres(# "type" character(1)
postgres(# );
CREATE TABLE
postgres=#
postgres=# insert into editions values("039480001X", 1608, 1, 59, "1957-03-01", "h");
INSERT 0 1
postgres=# insert into editions values("0451160916", 7808, 1, 75, "1981-08-01", "p");
INSERT 0 1
postgres=# insert into editions values("0394800753", 1590, 1, 59, "1949-03-01", "p");
INSERT 0 1
postgres=# insert into editions values("0590445065", 25908, 1, 150, "1987-03-01", "p");
INSERT 0 1
postgres=# insert into editions values("0694003611", 1501, 1, 65, "1947-03-04", "p");
INSERT 0 1
postgres=# insert into editions values("0679803335", 1234, 1, 102, "1922-01-01", "p");
INSERT 0 1
postgres=#
postgres=# select * from editions;
isbn | book_id | edition | publisher_id | publication | type
------------+---------+---------+--------------+-------------+------
039480001X | 1608 | 1 | 59 | 1957-03-01 | h
0451160916 | 7808 | 1 | 75 | 1981-08-01 | p
0394800753 | 1590 | 1 | 59 | 1949-03-01 | p
0590445065 | 25908 | 1 | 150 | 1987-03-01 | p
0694003611 | 1501 | 1 | 65 | 1947-03-04 | p
0679803335 | 1234 | 1 | 102 | 1922-01-01 | p
(6 rows)
postgres=#
postgres=# -- Using ORDER BY with multiple expressions
postgres=#
postgres=# SELECT edition, publication
postgres-# FROM editions
postgres-# ORDER BY edition ASC,
postgres-# publication DESC;
edition | publication
---------+-------------
1 | 1987-03-01
1 | 1981-08-01
1 | 1957-03-01
1 | 1949-03-01
1 | 1947-03-04
1 | 1922-01-01
(6 rows)
postgres=#
postgres=#
postgres=#
postgres=# drop table editions;
DROP TABLE
postgres=#
postgres=#

</source>

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в 13:45, 26 мая 2010

Admin: 1 версия