Mega Code Archive

Using LIMIT for Natural Join

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(# CONSTRAINT "integrity" CHECK (((book_id NOTNULL) AND (edition NOTNULL))), postgres(# Constraint "pkey" Primary Key ("isbn") postgres(# ); NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "pkey" for table "editions" 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 "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=# --Using LIMIT and OFFSET postgres=# postgres=# SELECT isbn, title, publication postgres-# FROM editions NATURAL JOIN books AS b (book_id) postgres-# ORDER BY publication DESC postgres-# LIMIT 5; isbn | title | publication ------------+--------------------+------------- 0596000855 | Programming Python | 2001-03-01 0451457994 | C# | 2000-09-12 044100590X | Javascript | 1999-10-01 0451198492 | C# | 1999-10-01 0929605942 | C++ | 1998-12-01 (5 rows) postgres=# postgres=# postgres=# postgres=# drop table books cascade; DROP TABLE postgres=# drop table editions cascade; DROP TABLE postgres=# postgres=#