PostgreSQL/View/Create View

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Creates a view of all publishers whose names begin with H

   <source lang="sql">

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=# -- Creates a view of all publishers whose names begin with H: postgres=# postgres=# CREATE VIEW h_publishers AS postgres-# SELECT * FROM publishers WHERE name LIKE "H%"; CREATE VIEW postgres=# postgres=# select * from h_publishers; 

id |    name    |         address
+------------+------------------------- 
91 | Henry Inc. | 115 Street New York, NY
65 | H Pubs     | 10 E 53rd St, New York

(2 rows) postgres=# postgres=# drop view h_publishers; DROP VIEW postgres=# drop table publishers; DROP TABLE postgres=# postgres=# 

      </source>


Create view from the user defined function

   <source lang="sql">

postgres=# postgres=# CREATE TABLE myTable ( postgres(# id int, postgres(# sid int, postgres(# name text); CREATE TABLE postgres=# postgres=# postgres=# insert into myTable values(1,2,"a"); INSERT 0 1 postgres=# insert into myTable values(2,3,"b"); INSERT 0 1 postgres=# postgres=# select * from myTable; 

id | sid | name
+-----+------ 
 1 |   2 | a
 2 |   3 | b

(2 rows) postgres=# postgres=# postgres=# postgres=# CREATE FUNCTION getData(int) RETURNS SETOF myTable AS $$ postgres$# SELECT * FROM myTable WHERE id = $1; postgres$# $$ LANGUAGE SQL; CREATE FUNCTION postgres=# postgres=# postgres=# CREATE VIEW vw_GetData AS SELECT * FROM getData(1); CREATE VIEW postgres=# postgres=# SELECT * FROM vw_GetData; 

id | sid | name
+-----+------ 
 1 |   2 | a

(1 row) postgres=# postgres=# drop function getData(int) cascade; NOTICE: drop cascades to rule _RETURN on view vw_getdata NOTICE: drop cascades to view vw_getdata DROP FUNCTION postgres=# drop view vw_GetData cascade; ERROR: view "vw_getdata" does not exist postgres=# drop table myTable cascade; DROP TABLE postgres=# postgres=# 

      </source>


Creating a view with a natural join statement

   <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(# 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=# CREATE TABLE "shipments" ( postgres(# "id" integer DEFAULT nextval(""shipments_ship_id_seq""::text) NOT NULL, postgres(# "customer_id" integer, postgres(# "isbn" text, postgres(# "ship_date" timestamp with time zone postgres(# ); CREATE TABLE postgres=# postgres=# insert into shipments values (375, 142, "039480001X","2004-01-06 09:19:21-01"); INSERT 0 1 postgres=# insert into shipments values (323, 671, "0451160916","2004-02-14 10:26:41-02"); INSERT 0 1 postgres=# insert into shipments values (998, 1045, "0590445065","2004-03-12 12:39:47-03"); INSERT 0 1 postgres=# insert into shipments values (749, 172, "0694003611","2003-04-11 10:42:34-04"); INSERT 0 1 postgres=# insert into shipments values (662, 655, "0679803335","2003-05-09 07:50:07-05"); INSERT 0 1 postgres=# insert into shipments values (806, 1125, "0760720002","2003-06-05 09:14:04-06"); INSERT 0 1 postgres=# insert into shipments values (102, 146, "0394900014","2002-07-11 13:24:08-07"); INSERT 0 1 postgres=# insert into shipments values (813, 112, "0385121679","2002-08-08 09:33:46-08"); INSERT 0 1 postgres=# insert into shipments values (652, 724, "1885418035","2002-09-14 13:41:39-09"); INSERT 0 1 postgres=# insert into shipments values (599, 430, "0929605942","2001-01-10 08:59:42-01"); INSERT 0 1 postgres=# insert into shipments values (969, 488, "0441172717","2006-02-14 08:12:58-02"); INSERT 0 1 postgres=# insert into shipments values (433, 898, "044100590X","2006-03-12 08:26:35-03"); INSERT 0 1 postgres=# insert into shipments values (660, 409, "0451457994","2006-04-07 11:36:42-04"); INSERT 0 1 postgres=# insert into shipments values (310, 738, "0451198492","2005-04-15 14:42:01-05"); INSERT 0 1 postgres=# insert into shipments values (510, 860, "0823015505","2005-05-14 07:53:47-06"); INSERT 0 1 postgres=# insert into shipments values (997, 185, "039480001X","2005-05-10 13:47:52-07"); INSERT 0 1 postgres=# insert into shipments values (999, 221, "0451160916","2005-06-14 13:45:51-08"); INSERT 0 1 postgres=# insert into shipments values (56, 880, "0590445065","2005-05-14 13:39:00-09"); INSERT 0 1 postgres=# insert into shipments values (72, 574, "0694003611","2004-04-06 07:29:44-00"); INSERT 0 1 postgres=# insert into shipments values (146, 270, "039480001X","2004-03-13 09:12:10-01"); INSERT 0 1 postgres=# insert into shipments values (981, 652, "0451160916","2003-02-08 08:46:44-02"); INSERT 0 1 postgres=# insert into shipments values (95, 480, "0590445065","2003-01-10 07:29:52-03"); INSERT 0 1 postgres=# insert into shipments values (593, 476, "0694003611","2002-03-15 11:17:40-04"); INSERT 0 1 postgres=# insert into shipments values (977, 853, "0679803335","2002-05-09 09:20:46-05"); INSERT 0 1 postgres=# insert into shipments values (117, 185, "0760720002","2005-05-07 13:30:48-06"); INSERT 0 1 postgres=# insert into shipments values (406, 1123, "0394900014","2004-04-13 09:41:04-07"); INSERT 0 1 postgres=# insert into shipments values (340, 1149, "0385121679","2003-02-12 13:21:22-08"); INSERT 0 1 postgres=# insert into shipments values (871, 388, "1885418035","2003-03-07 11:41:57-09"); INSERT 0 1 postgres=# insert into shipments values (1000, 221, "039480001X","2002-05-14 16:46:32-01"); INSERT 0 1 postgres=# insert into shipments values (1001, 107, "039480001X","2001-02-14 17:42:22-02"); INSERT 0 1 postgres=# insert into shipments values (754, 107, "0394800753","2006-05-11 09:55:05-03"); INSERT 0 1 postgres=# insert into shipments values (458, 107, "0394800753","2005-06-07 10:58:36-04"); INSERT 0 1 postgres=# insert into shipments values (189, 107, "0394800753","2004-03-06 11:46:36-04"); INSERT 0 1 postgres=# insert into shipments values (720, 107, "0394800753","2003-02-08 10:36:13-05"); INSERT 0 1 postgres=# insert into shipments values (1002, 107, "0394800753","2002-09-22 11:23:28-06"); INSERT 0 1 postgres=# insert into shipments values (2, 107, "0394800753","2001-09-22 20:18:56-07"); INSERT 0 1 postgres=# postgres=# select * from shipments; 

 id  | customer_id |    isbn    |       ship_date
+-------------+------------+------------------------ 
 375 |         142 | 039480001X | 2004-01-06 02:19:21-08
 323 |         671 | 0451160916 | 2004-02-14 04:26:41-08
 998 |        1045 | 0590445065 | 2004-03-12 07:39:47-08
 749 |         172 | 0694003611 | 2003-04-11 07:42:34-07
 662 |         655 | 0679803335 | 2003-05-09 05:50:07-07
 806 |        1125 | 0760720002 | 2003-06-05 08:14:04-07
 102 |         146 | 0394900014 | 2002-07-11 13:24:08-07
 813 |         112 | 0385121679 | 2002-08-08 10:33:46-07
 652 |         724 | 1885418035 | 2002-09-14 15:41:39-07
 599 |         430 | 0929605942 | 2001-01-10 01:59:42-08
 969 |         488 | 0441172717 | 2006-02-14 02:12:58-08
 433 |         898 | 044100590X | 2006-03-12 03:26:35-08
 660 |         409 | 0451457994 | 2006-04-07 08:36:42-07
 310 |         738 | 0451198492 | 2005-04-15 12:42:01-07
 510 |         860 | 0823015505 | 2005-05-14 06:53:47-07
 997 |         185 | 039480001X | 2005-05-10 13:47:52-07
 999 |         221 | 0451160916 | 2005-06-14 14:45:51-07
  56 |         880 | 0590445065 | 2005-05-14 15:39:00-07
  72 |         574 | 0694003611 | 2004-04-06 00:29:44-07
 146 |         270 | 039480001X | 2004-03-13 02:12:10-08
 981 |         652 | 0451160916 | 2003-02-08 02:46:44-08
  95 |         480 | 0590445065 | 2003-01-10 02:29:52-08
 593 |         476 | 0694003611 | 2002-03-15 07:17:40-08
 977 |         853 | 0679803335 | 2002-05-09 07:20:46-07
 117 |         185 | 0760720002 | 2005-05-07 12:30:48-07
 406 |        1123 | 0394900014 | 2004-04-13 09:41:04-07
 340 |        1149 | 0385121679 | 2003-02-12 13:21:22-08
 871 |         388 | 1885418035 | 2003-03-07 12:41:57-08
1000 |         221 | 039480001X | 2002-05-14 10:46:32-07
1001 |         107 | 039480001X | 2001-02-14 11:42:22-08
 754 |         107 | 0394800753 | 2006-05-11 05:55:05-07
 458 |         107 | 0394800753 | 2005-06-07 07:58:36-07
 189 |         107 | 0394800753 | 2004-03-06 07:46:36-08
 720 |         107 | 0394800753 | 2003-02-08 07:36:13-08
1002 |         107 | 0394800753 | 2002-09-22 10:23:28-07
   2 |         107 | 0394800753 | 2001-09-22 20:18:56-07

(36 rows) 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=# postgres=# postgres=# postgres=# -- Creating a view postgres=# postgres=# CREATE VIEW recent_shipments postgres-# AS SELECT count(*) AS num_shipped, max(ship_date), title postgres-# FROM shipments postgres-# JOIN editions USING (isbn) postgres-# NATURAL JOIN books AS b (book_id) postgres-# GROUP BY b.title postgres-# ORDER BY num_shipped DESC; CREATE VIEW postgres=# postgres=# select * from recent_shipments; 

num_shipped |          max           |    title
+------------------------+------------- 
          7 | 2005-05-10 13:47:52-07 | Oracle
          6 | 2006-05-11 05:55:05-07 | Sql Server
          5 | 2005-06-14 14:45:51-07 | Java
          3 | 2005-05-14 15:39:00-07 | Postgre SQL
          3 | 2004-04-06 00:29:44-07 | Python
          3 | 2003-03-07 12:41:57-08 | C++
          2 | 2003-05-09 05:50:07-07 | 2D
          2 | 2005-05-07 12:30:48-07 | Java by API
          2 | 2006-03-12 03:26:35-08 | Javascript
          2 | 2006-04-07 08:36:42-07 | C#
          1 | 2005-05-14 06:53:47-07 | C

(11 rows) postgres=# postgres=# SELECT * FROM recent_shipments postgres-# ORDER BY max DESC postgres-# LIMIT 3; 

num_shipped |          max           |   title
+------------------------+------------ 
          6 | 2006-05-11 05:55:05-07 | Sql Server
          2 | 2006-04-07 08:36:42-07 | C#
          2 | 2006-03-12 03:26:35-08 | Javascript

(3 rows) postgres=# postgres=# postgres=# postgres=# postgres=# drop view recent_shipments; DROP VIEW postgres=# postgres=# drop table books; DROP TABLE postgres=# drop table editions; DROP TABLE postgres=# drop table shipments; DROP TABLE postgres=# postgres=# 

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