PostgreSQL/Postgre SQL/ROWTYPE

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ROWTYPE assign through "select into"

   <source lang="sql">

postgres=# 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=# CREATE FUNCTION "get_data" (integer) RETURNS text AS " postgres"# DECLARE postgres"# -- Declare an alias for the function argument, postgres"# eid ALIAS FOR $1; postgres"# found_employee employee%ROWTYPE; postgres"# BEGIN postgres"# SELECT INTO found_employee * FROM employee WHERE id = eid; postgres"# RETURN found_employee.name || "" "" || found_employee.city; postgres"# END; postgres"# " LANGUAGE "plpgsql"; CREATE FUNCTION postgres=# postgres=# select get_data(id) from employee; 

    get_data

Jason New York
Robert Vancouver
Celia Toronto
Linda New York
David Vancouver
James Toronto
Alison New York
Chris Vancouver
Mary Toronto

(9 rows) postgres=# postgres=# drop function get_data (integer); DROP FUNCTION postgres=# drop table employee; DROP TABLE postgres=# postgres=# postgres=# 

      </source>


Using the FOR loop with %ROWTYPE

   <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=# postgres=# -- Using the FOR loop with %ROWTYPE postgres=# postgres=# CREATE FUNCTION extract_title (integer) RETURNS text AS " postgres"# DECLARE postgres"# postgres"# -- Declare an alias for function argument. postgres"# sub_id ALIAS FOR $1; postgres"# postgres"# -- Declare a variable to hold book titles and set its default postgres"# -- value to a new line. postgres"# text_output TEXT :=""\n""; postgres"# postgres"# -- Declare a variable to hold rows from the postgres"# -- books table. postgres"# row_data books%ROWTYPE; postgres"# postgres"# BEGIN postgres"# postgres"# -- Iterate through the results of a query. postgres"# FOR row_data IN SELECT * FROM books postgres"# WHERE subject_id = sub_id ORDER BY title LOOP postgres"# postgres"# -- Insert the title of a matching book into the text_output variable. postgres"# text_output := text_output || row_data.title || ""\n""; postgres"# END LOOP; postgres"# postgres"# -- Return the list of books. postgres"# RETURN text_output; postgres"# END; postgres"# " LANGUAGE "plpgsql"; ERROR: function "extract_title" already exists with same argument types postgres=# postgres=# postgres=# SELECT extract_title(2); 

extract_title

Sql Server

(1 row) postgres=# postgres=# postgres=# drop table books; DROP TABLE postgres=# postgres=# 

      </source>


Using the %ROWTYPE attribute

   <source lang="sql">

postgres=# 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=# postgres=# postgres=# -- Using the %ROWTYPE attribute postgres=# postgres=# CREATE FUNCTION get_author (integer) RETURNS text AS " postgres"# DECLARE postgres"# postgres"# -- Declare an alias for the function argument, postgres"# -- which should be the id of the author. postgres"# author_id ALIAS FOR $1; postgres"# postgres"# found_author authors%ROWTYPE; postgres"# postgres"# BEGIN postgres"# SELECT INTO found_author * FROM authors WHERE id = author_id; postgres"# postgres"# -- Return the first postgres"# RETURN found_author.first_name || "" "" || found_author.last_name; postgres"# postgres"# END; postgres"# " LANGUAGE "plpgsql"; CREATE FUNCTION postgres=# postgres=# -- Results of the new get_author() function postgres=# postgres=# SELECT get_author(1212); 

  get_author

Robert Worsley

(1 row) postgres=# postgres=# postgres=# drop table authors; DROP TABLE postgres=# postgres=# 

      </source>
Источник — «http://sqle.ru/index.php?title=PostgreSQL/Postgre_SQL/ROWTYPE&oldid=4548»