PostgreSQL/Table Joins/Table Join
Содержание
Aliasing columns
<source lang="sql">
postgres=# postgres=# postgres=# CREATE TABLE "books" ( postgres(# "id" integer NOT NULL, postgres(# "title" text NOT NULL, postgres(# "author_id" integer, postgres(# "subject_id" integer, postgres(# Constraint "books_id_pkey" Primary Key ("id") postgres(# ); NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "books_id_pkey" for table "books" CREATE TABLE postgres=# postgres=# postgres=# insert into books values (7808, "Java", 4156, 9); INSERT 0 1 postgres=# insert into books values (4513, "Javascript", 1866, 15); INSERT 0 1 postgres=# insert into books values (4267, "C#", 2001, 15); INSERT 0 1 postgres=# insert into books values (1608, "Oracle", 1809, 2); INSERT 0 1 postgres=# insert into books values (1590, "Sql Server", 1809, 2); INSERT 0 1 postgres=# insert into books values (25908, "Postgre SQL", 15990, 2); INSERT 0 1 postgres=# insert into books values (1501, "Python", 2031, 2); INSERT 0 1 postgres=# insert into books values (190, "Java by API", 16, 6); INSERT 0 1 postgres=# insert into books values (1234, "2D", 25041, 3); INSERT 0 1 postgres=# insert into books values (2038, "C", 1644, 0); INSERT 0 1 postgres=# insert into books values (156, "C++", 115, 9); INSERT 0 1 postgres=# insert into books values (41473, "Programming Python", 7805, 4); INSERT 0 1 postgres=# insert into books values (41477, "Learning Python", 7805, 4); INSERT 0 1 postgres=# insert into books values (41478, "Perl Cookbook", 7806, 4); INSERT 0 1 postgres=# insert into books values (41472, "Practical PostgreSQL", 1212, 4); INSERT 0 1 postgres=# postgres=# select * from books;
id | title | author_id | subject_id
+----------------------+-----------+------------
7808 | Java | 4156 | 9 4513 | Javascript | 1866 | 15 4267 | C# | 2001 | 15 1608 | Oracle | 1809 | 2 1590 | Sql Server | 1809 | 2 25908 | Postgre SQL | 15990 | 2 1501 | Python | 2031 | 2 190 | Java by API | 16 | 6 1234 | 2D | 25041 | 3 2038 | C | 1644 | 0 156 | C++ | 115 | 9 41473 | Programming Python | 7805 | 4 41477 | Learning Python | 7805 | 4 41478 | Perl Cookbook | 7806 | 4 41472 | Practical PostgreSQL | 1212 | 4
(15 rows) 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=# insert into authors values (1111, "Martin", "Jason"); INSERT 0 1 postgres=# insert into authors values (1212, "Worsley", "Robert"); INSERT 0 1 postgres=# insert into authors values (15990, "Mathews", "John"); INSERT 0 1 postgres=# insert into authors values (25041, "Smith", "Williams"); INSERT 0 1 postgres=# insert into authors values (16, "Alcott", "May"); INSERT 0 1 postgres=# insert into authors values (4156, "King", "Stephen"); INSERT 0 1 postgres=# insert into authors values (1866, "Herbert", "Margaret"); INSERT 0 1 postgres=# insert into authors values (1644, "Hogarth", "Celia"); INSERT 0 1 postgres=# insert into authors values (2031, "Brown", "Wise"); INSERT 0 1 postgres=# insert into authors values (115, "Poe", "Allen"); INSERT 0 1 postgres=# insert into authors values (7805, "Lutz", "Mark"); INSERT 0 1 postgres=# insert into authors values (7806, "Rice", "Tom"); INSERT 0 1 postgres=# insert into authors values (1533, "Black", "Chris"); INSERT 0 1 postgres=# insert into authors values (1717, "Brite", "Linda"); INSERT 0 1 postgres=# insert into authors values (2112, "Larry", "Edward"); INSERT 0 1 postgres=# insert into authors values (2001, "Clarke", "Alison"); INSERT 0 1 postgres=# insert into authors values (1213, "Green", "Mary"); INSERT 0 1 postgres=# postgres=# select * from authors;
id | last_name | first_name
+-----------+------------
1111 | Martin | Jason 1212 | Worsley | Robert 15990 | Mathews | John 25041 | Smith | Williams 16 | Alcott | May 4156 | King | Stephen 1866 | Herbert | Margaret 1644 | Hogarth | Celia 2031 | Brown | Wise 115 | Poe | Allen 7805 | Lutz | Mark 7806 | Rice | Tom 1533 | Black | Chris 1717 | Brite | Linda 2112 | Larry | Edward 2001 | Clarke | Alison 1213 | Green | Mary
(17 rows) postgres=# postgres=# -- Aliasing columns postgres=# postgres=# SELECT the_book_id, title, id, last_name postgres-# FROM books AS b (the_book_id), authors postgres-# WHERE author_id = id;
the_book_id | title | id | last_name
+----------------------+-------+-----------
7808 | Java | 4156 | King 4513 | Javascript | 1866 | Herbert 4267 | C# | 2001 | Clarke 25908 | Postgre SQL | 15990 | Mathews 1501 | Python | 2031 | Brown 190 | Java by API | 16 | Alcott 1234 | 2D | 25041 | Smith 2038 | C | 1644 | Hogarth 156 | C++ | 115 | Poe 41473 | Programming Python | 7805 | Lutz 41477 | Learning Python | 7805 | Lutz 41478 | Perl Cookbook | 7806 | Rice 41472 | Practical PostgreSQL | 1212 | Worsley
(13 rows) postgres=# postgres=# postgres=# postgres=# drop table authors; DROP TABLE postgres=# drop table books; DROP TABLE postgres=# postgres=#
</source>
Aliasing FROM sources
<source lang="sql">
postgres=# postgres=# CREATE TABLE "books" ( postgres(# "id" integer NOT NULL, postgres(# "title" text NOT NULL, postgres(# "author_id" integer, postgres(# "subject_id" integer, postgres(# Constraint "books_id_pkey" Primary Key ("id") postgres(# ); NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "books_id_pkey" for table "books" CREATE TABLE postgres=# postgres=# postgres=# insert into books values (7808, "Java", 4156, 9); INSERT 0 1 postgres=# insert into books values (4513, "Javascript", 1866, 15); INSERT 0 1 postgres=# insert into books values (4267, "C#", 2001, 15); INSERT 0 1 postgres=# insert into books values (1608, "Oracle", 1809, 2); INSERT 0 1 postgres=# insert into books values (1590, "Sql Server", 1809, 2); INSERT 0 1 postgres=# insert into books values (25908, "Postgre SQL", 15990, 2); INSERT 0 1 postgres=# insert into books values (1501, "Python", 2031, 2); INSERT 0 1 postgres=# insert into books values (190, "Java by API", 16, 6); INSERT 0 1 postgres=# insert into books values (1234, "2D", 25041, 3); INSERT 0 1 postgres=# insert into books values (2038, "C", 1644, 0); INSERT 0 1 postgres=# insert into books values (156, "C++", 115, 9); INSERT 0 1 postgres=# insert into books values (41473, "Programming Python", 7805, 4); INSERT 0 1 postgres=# insert into books values (41477, "Learning Python", 7805, 4); INSERT 0 1 postgres=# insert into books values (41478, "Perl Cookbook", 7806, 4); INSERT 0 1 postgres=# insert into books values (41472, "Practical PostgreSQL", 1212, 4); INSERT 0 1 postgres=# postgres=# select * from books;
id | title | author_id | subject_id
+----------------------+-----------+------------
7808 | Java | 4156 | 9 4513 | Javascript | 1866 | 15 4267 | C# | 2001 | 15 1608 | Oracle | 1809 | 2 1590 | Sql Server | 1809 | 2 25908 | Postgre SQL | 15990 | 2 1501 | Python | 2031 | 2 190 | Java by API | 16 | 6 1234 | 2D | 25041 | 3 2038 | C | 1644 | 0 156 | C++ | 115 | 9 41473 | Programming Python | 7805 | 4 41477 | Learning Python | 7805 | 4 41478 | Perl Cookbook | 7806 | 4 41472 | Practical PostgreSQL | 1212 | 4
(15 rows) 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=# insert into authors values (1111, "Martin", "Jason"); INSERT 0 1 postgres=# insert into authors values (1212, "Worsley", "Robert"); INSERT 0 1 postgres=# insert into authors values (15990, "Mathews", "John"); INSERT 0 1 postgres=# insert into authors values (25041, "Smith", "Williams"); INSERT 0 1 postgres=# insert into authors values (16, "Alcott", "May"); INSERT 0 1 postgres=# insert into authors values (4156, "King", "Stephen"); INSERT 0 1 postgres=# insert into authors values (1866, "Herbert", "Margaret"); INSERT 0 1 postgres=# insert into authors values (1644, "Hogarth", "Celia"); INSERT 0 1 postgres=# insert into authors values (2031, "Brown", "Wise"); INSERT 0 1 postgres=# insert into authors values (115, "Poe", "Allen"); INSERT 0 1 postgres=# insert into authors values (7805, "Lutz", "Mark"); INSERT 0 1 postgres=# insert into authors values (7806, "Rice", "Tom"); INSERT 0 1 postgres=# insert into authors values (1533, "Black", "Chris"); INSERT 0 1 postgres=# insert into authors values (1717, "Brite", "Linda"); INSERT 0 1 postgres=# insert into authors values (2112, "Larry", "Edward"); INSERT 0 1 postgres=# insert into authors values (2001, "Clarke", "Alison"); INSERT 0 1 postgres=# insert into authors values (1213, "Green", "Mary"); INSERT 0 1 postgres=# postgres=# select * from authors;
id | last_name | first_name
+-----------+------------
1111 | Martin | Jason 1212 | Worsley | Robert 15990 | Mathews | John 25041 | Smith | Williams 16 | Alcott | May 4156 | King | Stephen 1866 | Herbert | Margaret 1644 | Hogarth | Celia 2031 | Brown | Wise 115 | Poe | Allen 7805 | Lutz | Mark 7806 | Rice | Tom 1533 | Black | Chris 1717 | Brite | Linda 2112 | Larry | Edward 2001 | Clarke | Alison 1213 | Green | Mary
(17 rows) postgres=# postgres=# -- Aliasing FROM sources postgres=# postgres=# SELECT b.id, title, a.id, last_name postgres-# FROM books AS b, authors AS a postgres-# WHERE b.author_id = a.id;
id | title | id | last_name
+----------------------+-------+-----------
7808 | Java | 4156 | King 4513 | Javascript | 1866 | Herbert 4267 | C# | 2001 | Clarke 25908 | Postgre SQL | 15990 | Mathews 1501 | Python | 2031 | Brown 190 | Java by API | 16 | Alcott 1234 | 2D | 25041 | Smith 2038 | C | 1644 | Hogarth 156 | C++ | 115 | Poe 41473 | Programming Python | 7805 | Lutz 41477 | Learning Python | 7805 | Lutz 41478 | Perl Cookbook | 7806 | Rice 41472 | Practical PostgreSQL | 1212 | Worsley
(13 rows) postgres=# postgres=# postgres=# postgres=# drop table authors; DROP TABLE postgres=# drop table books; DROP TABLE postgres=# postgres=#
</source>
Join three tables together
<source lang="sql">
postgres=# 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=# insert into editions values("0760720002", 190, 1, 91, "1868-01-01", "p"); INSERT 0 1 postgres=# insert into editions values("0394900014", 1608, 1, 59, "1957-01-01", "p"); INSERT 0 1 postgres=# insert into editions values("0385121679", 7808, 2, 75, "1993-10-01", "h"); INSERT 0 1 postgres=# insert into editions values("1885418035", 156, 1, 163, "1995-03-28", "p"); INSERT 0 1 postgres=# insert into editions values("0929605942", 156, 2, 171, "1998-12-01", "p"); INSERT 0 1 postgres=# insert into editions values("0441172717", 4513, 2, 99, "1998-09-01", "p"); INSERT 0 1 postgres=# insert into editions values("044100590X", 4513, 3, 99, "1999-10-01", "h"); INSERT 0 1 postgres=# insert into editions values("0451457994", 4267, 3, 101, "2000-09-12", "p"); INSERT 0 1 postgres=# insert into editions values("0451198492", 4267, 3, 101, "1999-10-01", "h"); INSERT 0 1 postgres=# insert into editions values("0823015505", 2038, 1, 62, "1958-01-01", "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 0679803335 | 1234 | 1 | 102 | 1922-01-01 | p 0760720002 | 190 | 1 | 91 | 1868-01-01 | p 0394900014 | 1608 | 1 | 59 | 1957-01-01 | p 0385121679 | 7808 | 2 | 75 | 1993-10-01 | h 1885418035 | 156 | 1 | 163 | 1995-03-28 | p 0929605942 | 156 | 2 | 171 | 1998-12-01 | p 0441172717 | 4513 | 2 | 99 | 1998-09-01 | p 044100590X | 4513 | 3 | 99 | 1999-10-01 | h 0451457994 | 4267 | 3 | 101 | 2000-09-12 | p 0451198492 | 4267 | 3 | 101 | 1999-10-01 | h 0823015505 | 2038 | 1 | 62 | 1958-01-01 | p 0596000855 | 41473 | 2 | 113 | 2001-03-01 | p
(17 rows) postgres=# postgres=# postgres=# CREATE TABLE "publishers" ( postgres(# "id" integer NOT NULL, postgres(# "name" text, postgres(# "address" text, postgres(# Constraint "publishers_pkey" Primary Key ("id") postgres(# ); postgres=# postgres=# postgres=# insert into publishers values(150, "Can Press", "29 Ave. Toronto, ON"); postgres=# insert into publishers values(91, "Henry Inc.", "115 Street New York, NY"); postgres=# insert into publishers values(113, "O Inc.", "101 St, Sebastopol, CA"); postgres=# insert into publishers values(62, "W Pubs", "1515, New York"); postgres=# insert into publishers values(105, "N Press", "19 W, New York"); postgres=# insert into publishers values(99, "A Inc", "375 St, New York"); postgres=# insert into publishers values(101, "Z Inc", "375 Ave, New York"); postgres=# insert into publishers values(163, "M Press", "PO Box 1215"); postgres=# insert into publishers values(171, "B", "16 W. 18th St. New York"); postgres=# insert into publishers values(102, "P Inc", "375 Hudson St, New York"); postgres=# insert into publishers values(75, "D Inc", "1540 Broadway, New York"); postgres=# insert into publishers values(65, "H Pubs", "10 E 53rd St, New York"); postgres=# insert into publishers values(59, "R Inc", "1540 Broadway, New York"); postgres=# postgres=# select * from publishers;
id | name | address
+------------+-------------------------
150 | Can Press | 29 Ave. Toronto, ON 91 | Henry Inc. | 115 Street New York, NY 113 | O Inc. | 101 St, Sebastopol, CA 62 | W Pubs | 1515, New York 105 | N Press | 19 W, New York 99 | A Inc | 375 St, New York 101 | Z Inc | 375 Ave, New York 163 | M Press | PO Box 1215 171 | B | 16 W. 18th St. New York 102 | P Inc | 375 Hudson St, New York 75 | D Inc | 1540 Broadway, New York 65 | H Pubs | 10 E 53rd St, New York 59 | R Inc | 1540 Broadway, New York
(13 rows) postgres=# postgres=# postgres=# CREATE TABLE "stock" ( postgres(# "isbn" text NOT NULL, postgres(# "cost" numeric(5,2), postgres(# "retail" numeric(5,2), postgres(# "stock" integer, postgres(# Constraint "stock_pkey" Primary Key ("isbn") postgres(# ); NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "stock_pkey" for table "stock" CREATE TABLE postgres=# postgres=# postgres=# insert into stock values ("0385121679", 29.00, 36.95, 65); INSERT 0 1 postgres=# insert into stock values ("039480001X", 30.00, 32.95, 31); INSERT 0 1 postgres=# insert into stock values ("0394900014", 23.00, 23.95, 0); INSERT 0 1 postgres=# insert into stock values ("044100590X", 36.00, 45.95, 89); INSERT 0 1 postgres=# insert into stock values ("0441172717", 17.00, 21.95, 77); INSERT 0 1 postgres=# insert into stock values ("0451160916", 24.00, 28.95, 22); INSERT 0 1 postgres=# insert into stock values ("0451198492", 36.00, 46.95, 0); INSERT 0 1 postgres=# insert into stock values ("0451457994", 17.00, 22.95, 0); INSERT 0 1 postgres=# insert into stock values ("0590445065", 23.00, 23.95, 10); INSERT 0 1 postgres=# insert into stock values ("0679803335", 20.00, 24.95, 18); INSERT 0 1 postgres=# insert into stock values ("0694003611", 25.00, 28.95, 50); INSERT 0 1 postgres=# insert into stock values ("0760720002", 18.00, 23.95, 28); INSERT 0 1 postgres=# insert into stock values ("0823015505", 26.00, 28.95, 16); INSERT 0 1 postgres=# insert into stock values ("0929605942", 19.00, 21.95, 25); INSERT 0 1 postgres=# insert into stock values ("1885418035", 23.00, 24.95, 77); INSERT 0 1 postgres=# insert into stock values ("0394800753", 16.00, 16.95, 4); INSERT 0 1 postgres=# postgres=# select * FROM stock;
isbn | cost | retail | stock
+-------+--------+-------
0385121679 | 29.00 | 36.95 | 65 039480001X | 30.00 | 32.95 | 31 0394900014 | 23.00 | 23.95 | 0 044100590X | 36.00 | 45.95 | 89 0441172717 | 17.00 | 21.95 | 77 0451160916 | 24.00 | 28.95 | 22 0451198492 | 36.00 | 46.95 | 0 0451457994 | 17.00 | 22.95 | 0 0590445065 | 23.00 | 23.95 | 10 0679803335 | 20.00 | 24.95 | 18 0694003611 | 25.00 | 28.95 | 50 0760720002 | 18.00 | 23.95 | 28 0823015505 | 26.00 | 28.95 | 16 0929605942 | 19.00 | 21.95 | 25 1885418035 | 23.00 | 24.95 | 77 0394800753 | 16.00 | 16.95 | 4
(16 rows) postgres=# postgres=# postgres=# postgres=# postgres=# SELECT avg(cost) AS average_cost, p.name AS publisher postgres-# FROM (stock JOIN editions USING (isbn)) postgres-# JOIN publishers AS p (publisher_id) postgres-# USING (publisher_id) postgres-# GROUP BY p.name;
average_cost | publisher
+------------
19.0000000000000000 | B 26.5000000000000000 | D Inc 26.5000000000000000 | A Inc 25.0000000000000000 | H Pubs 26.0000000000000000 | W Pubs 20.0000000000000000 | P Inc 26.5000000000000000 | Z Inc 23.0000000000000000 | Can Press 23.0000000000000000 | R Inc 23.0000000000000000 | M Press 18.0000000000000000 | Henry Inc.
(11 rows) postgres=# postgres=# drop table publishers; DROP TABLE postgres=# drop table editions; DROP TABLE postgres=#
</source>
Join two tables with order by and group by
<source lang="sql">
postgres=# 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=# insert into editions values("0760720002", 190, 1, 91, "1868-01-01", "p"); INSERT 0 1 postgres=# insert into editions values("0394900014", 1608, 1, 59, "1957-01-01", "p"); INSERT 0 1 postgres=# insert into editions values("0385121679", 7808, 2, 75, "1993-10-01", "h"); INSERT 0 1 postgres=# insert into editions values("1885418035", 156, 1, 163, "1995-03-28", "p"); INSERT 0 1 postgres=# insert into editions values("0929605942", 156, 2, 171, "1998-12-01", "p"); INSERT 0 1 postgres=# insert into editions values("0441172717", 4513, 2, 99, "1998-09-01", "p"); INSERT 0 1 postgres=# insert into editions values("044100590X", 4513, 3, 99, "1999-10-01", "h"); INSERT 0 1 postgres=# insert into editions values("0451457994", 4267, 3, 101, "2000-09-12", "p"); INSERT 0 1 postgres=# insert into editions values("0451198492", 4267, 3, 101, "1999-10-01", "h"); INSERT 0 1 postgres=# insert into editions values("0823015505", 2038, 1, 62, "1958-01-01", "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 0679803335 | 1234 | 1 | 102 | 1922-01-01 | p 0760720002 | 190 | 1 | 91 | 1868-01-01 | p 0394900014 | 1608 | 1 | 59 | 1957-01-01 | p 0385121679 | 7808 | 2 | 75 | 1993-10-01 | h 1885418035 | 156 | 1 | 163 | 1995-03-28 | p 0929605942 | 156 | 2 | 171 | 1998-12-01 | p 0441172717 | 4513 | 2 | 99 | 1998-09-01 | p 044100590X | 4513 | 3 | 99 | 1999-10-01 | h 0451457994 | 4267 | 3 | 101 | 2000-09-12 | p 0451198492 | 4267 | 3 | 101 | 1999-10-01 | h 0823015505 | 2038 | 1 | 62 | 1958-01-01 | p 0596000855 | 41473 | 2 | 113 | 2001-03-01 | p
(17 rows) postgres=# postgres=# postgres=# CREATE TABLE "publishers" ( postgres(# "id" integer NOT NULL, postgres(# "name" text, postgres(# "address" text, postgres(# Constraint "publishers_pkey" Primary Key ("id") postgres(# ); NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "publishers_pkey" for table "publishers" CREATE TABLE postgres=# postgres=# postgres=# insert into publishers values(150, "Can Press", "29 Ave. Toronto, ON"); INSERT 0 1 postgres=# insert into publishers values(91, "Henry Inc.", "115 Street New York, NY"); INSERT 0 1 postgres=# insert into publishers values(113, "O Inc.", "101 St, Sebastopol, CA"); INSERT 0 1 postgres=# insert into publishers values(62, "W Pubs", "1515, New York"); INSERT 0 1 postgres=# insert into publishers values(105, "N Press", "19 W, New York"); INSERT 0 1 postgres=# insert into publishers values(99, "A Inc", "375 St, New York"); INSERT 0 1 postgres=# insert into publishers values(101, "Z Inc", "375 Ave, New York"); INSERT 0 1 postgres=# insert into publishers values(163, "M Press", "PO Box 1215"); INSERT 0 1 postgres=# insert into publishers values(171, "B", "16 W. 18th St. New York"); INSERT 0 1 postgres=# insert into publishers values(102, "P Inc", "375 Hudson St, New York"); INSERT 0 1 postgres=# insert into publishers values(75, "D Inc", "1540 Broadway, New York"); INSERT 0 1 postgres=# insert into publishers values(65, "H Pubs", "10 E 53rd St, New York"); INSERT 0 1 postgres=# insert into publishers values(59, "R Inc", "1540 Broadway, New York"); INSERT 0 1 postgres=# postgres=# select * from publishers;
id | name | address
+------------+-------------------------
150 | Can Press | 29 Ave. Toronto, ON 91 | Henry Inc. | 115 Street New York, NY 113 | O Inc. | 101 St, Sebastopol, CA 62 | W Pubs | 1515, New York 105 | N Press | 19 W, New York 99 | A Inc | 375 St, New York 101 | Z Inc | 375 Ave, New York 163 | M Press | PO Box 1215 171 | B | 16 W. 18th St. New York 102 | P Inc | 375 Hudson St, New York 75 | D Inc | 1540 Broadway, New York 65 | H Pubs | 10 E 53rd St, New York 59 | R Inc | 1540 Broadway, New York
(13 rows) postgres=# postgres=# SELECT count(book_id), p.name postgres-# FROM editions JOIN publishers AS p (publisher_id) postgres-# USING (publisher_id) postgres-# GROUP BY p.name postgres-# ORDER BY count DESC;
count | name
+------------
3 | R Inc 2 | Z Inc 2 | A Inc 2 | D Inc 1 | W Pubs 1 | P Inc 1 | H Pubs 1 | O Inc. 1 | Can Press 1 | B 1 | M Press 1 | Henry Inc.
(12 rows) postgres=# postgres=# drop table editions; DROP TABLE postgres=# drop table publishers; DROP TABLE postgres=#
</source>
Selecting from multiple table sources
<source lang="sql">
postgres=# postgres=# postgres=# postgres=# postgres=# postgres=# postgres=# CREATE TABLE "books" ( postgres(# "id" integer NOT NULL, postgres(# "title" text NOT NULL, postgres(# "author_id" integer, postgres(# "subject_id" integer, postgres(# Constraint "books_id_pkey" Primary Key ("id") postgres(# ); NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "books_id_pkey" for table "books" CREATE TABLE postgres=# postgres=# postgres=# insert into books values (7808, "Java", 4156, 9); INSERT 0 1 postgres=# insert into books values (4513, "Javascript", 1866, 15); INSERT 0 1 postgres=# insert into books values (4267, "C#", 2001, 15); INSERT 0 1 postgres=# insert into books values (1608, "Oracle", 1809, 2); INSERT 0 1 postgres=# insert into books values (1590, "Sql Server", 1809, 2); INSERT 0 1 postgres=# insert into books values (25908, "Postgre SQL", 15990, 2); INSERT 0 1 postgres=# insert into books values (1501, "Python", 2031, 2); INSERT 0 1 postgres=# insert into books values (190, "Java by API", 16, 6); INSERT 0 1 postgres=# insert into books values (1234, "2D", 25041, 3); INSERT 0 1 postgres=# insert into books values (2038, "C", 1644, 0); INSERT 0 1 postgres=# insert into books values (156, "C++", 115, 9); INSERT 0 1 postgres=# insert into books values (41473, "Programming Python", 7805, 4); INSERT 0 1 postgres=# insert into books values (41477, "Learning Python", 7805, 4); INSERT 0 1 postgres=# insert into books values (41478, "Perl Cookbook", 7806, 4); INSERT 0 1 postgres=# insert into books values (41472, "Practical PostgreSQL", 1212, 4); INSERT 0 1 postgres=# postgres=# select * from books;
id | title | author_id | subject_id
+----------------------+-----------+------------
7808 | Java | 4156 | 9 4513 | Javascript | 1866 | 15 4267 | C# | 2001 | 15 1608 | Oracle | 1809 | 2 1590 | Sql Server | 1809 | 2 25908 | Postgre SQL | 15990 | 2 1501 | Python | 2031 | 2 190 | Java by API | 16 | 6 1234 | 2D | 25041 | 3 2038 | C | 1644 | 0 156 | C++ | 115 | 9 41473 | Programming Python | 7805 | 4 41477 | Learning Python | 7805 | 4 41478 | Perl Cookbook | 7806 | 4 41472 | Practical PostgreSQL | 1212 | 4
(15 rows) 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=# insert into authors values (1111, "Martin", "Jason"); INSERT 0 1 postgres=# insert into authors values (1212, "Worsley", "Robert"); INSERT 0 1 postgres=# insert into authors values (15990, "Mathews", "John"); INSERT 0 1 postgres=# insert into authors values (25041, "Smith", "Williams"); INSERT 0 1 postgres=# insert into authors values (16, "Alcott", "May"); INSERT 0 1 postgres=# insert into authors values (4156, "King", "Stephen"); INSERT 0 1 postgres=# insert into authors values (1866, "Herbert", "Margaret"); INSERT 0 1 postgres=# insert into authors values (1644, "Hogarth", "Celia"); INSERT 0 1 postgres=# insert into authors values (2031, "Brown", "Wise"); INSERT 0 1 postgres=# insert into authors values (115, "Poe", "Allen"); INSERT 0 1 postgres=# insert into authors values (7805, "Lutz", "Mark"); INSERT 0 1 postgres=# insert into authors values (7806, "Rice", "Tom"); INSERT 0 1 postgres=# insert into authors values (1533, "Black", "Chris"); INSERT 0 1 postgres=# insert into authors values (1717, "Brite", "Linda"); INSERT 0 1 postgres=# insert into authors values (2112, "Larry", "Edward"); INSERT 0 1 postgres=# insert into authors values (2001, "Clarke", "Alison"); INSERT 0 1 postgres=# insert into authors values (1213, "Green", "Mary"); INSERT 0 1 postgres=# postgres=# select * from authors;
id | last_name | first_name
+-----------+------------
1111 | Martin | Jason 1212 | Worsley | Robert 15990 | Mathews | John 25041 | Smith | Williams 16 | Alcott | May 4156 | King | Stephen 1866 | Herbert | Margaret 1644 | Hogarth | Celia 2031 | Brown | Wise 115 | Poe | Allen 7805 | Lutz | Mark 7806 | Rice | Tom 1533 | Black | Chris 1717 | Brite | Linda 2112 | Larry | Edward 2001 | Clarke | Alison 1213 | Green | Mary
(17 rows) postgres=# postgres=# -- Selecting from multiple table sources postgres=# postgres=# SELECT books.id, title, authors.id, last_name postgres-# FROM books, authors postgres-# WHERE books.author_id = authors.id;
id | title | id | last_name
+----------------------+-------+-----------
7808 | Java | 4156 | King 4513 | Javascript | 1866 | Herbert 4267 | C# | 2001 | Clarke 25908 | Postgre SQL | 15990 | Mathews 1501 | Python | 2031 | Brown 190 | Java by API | 16 | Alcott 1234 | 2D | 25041 | Smith 2038 | C | 1644 | Hogarth 156 | C++ | 115 | Poe 41473 | Programming Python | 7805 | Lutz 41477 | Learning Python | 7805 | Lutz 41478 | Perl Cookbook | 7806 | Rice 41472 | Practical PostgreSQL | 1212 | Worsley
(13 rows) postgres=# postgres=# postgres=# postgres=# drop table authors; DROP TABLE postgres=# drop table books; DROP TABLE
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