PostgreSQL/Data Type/text

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Declare Text type variable

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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 SELECT INTO with multiple columns postgres=# postgres=# CREATE FUNCTION get_data (integer) RETURNS text AS " postgres"# DECLARE postgres"# postgres"# -- Declare aliases for user input. postgres"# e_id ALIAS FOR $1; postgres"# postgres"# -- Declare variables to hold the customer name. postgres"# fname TEXT; postgres"# cityname TEXT; postgres"# postgres"# BEGIN postgres"# SELECT INTO fname, cityname postgres"# name, city postgres"# FROM employee WHERE id = e_id; postgres"# postgres"# -- If a match could not be found, return -1 (another function calling postgres"# -- this function could then be made to interpret a -1 as an error. postgres"# IF NOT FOUND THEN postgres"# return -1; postgres"# END IF; postgres"# postgres"# -- Return the name. postgres"# RETURN fname || "" "" || cityname; postgres"# postgres"# END; postgres"# " LANGUAGE "plpgsql"; CREATE FUNCTION postgres=# postgres=# SELECT get_data(107);

get_data

-1

(1 row) postgres=# postgres=# postgres=# drop function get_data(integer); DROP FUNCTION postgres=# drop table employee; DROP TABLE postgres=#

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Using Type Conversion Functions

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postgres=# postgres=# -- Using Type Conversion Functions postgres=# postgres=# SELECT text(1000) AS explicit_text;

explicit_text

1000

(1 row) postgres=#

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