PostgreSQL/Insert Delete Update/Insert Select

Insert into by select statement

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 TABLE employee_backup (
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_backup SELECT * FROM employee;
INSERT 0 9
postgres=#
postgres=# select * from employee_backup;
 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=# drop table employee;
DROP TABLE
postgres=# drop table employee_backup;
DROP TABLE
postgres=#
postgres=#

INSERT INTO vv SELECT "abc" || "def"

postgres=#
postgres=# CREATE TABLE vv (v character(20));
CREATE TABLE
postgres=#
postgres=# INSERT INTO vv SELECT "abc" || "def";
INSERT 0 1
postgres=# SELECT v, length(v) FROM vv;
          v           | length
----------------------+--------
 abcdef               |      6
(1 row)
postgres=#
postgres=# drop table vv;
DROP TABLE
postgres=#

Restructuring a table with CREATE TABLE and INSERT INTO

postgres=# CREATE TABLE books (
postgres(#               id integer UNIQUE,
postgres(#               title text NOT NULL,
postgres(#               author_id  integer,
postgres(#               subject_id integer);
NOTICE:  CREATE TABLE / UNIQUE will create implicit index "books_id_key" 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=#
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
(8 rows)
postgres=#
postgres=# --Restructuring a table with CREATE TABLE and INSERT INTO
postgres=#
postgres=# CREATE TABLE new_books (
postgres(#    id integer UNIQUE,
postgres(#    title text NOT NULL,
postgres(#    author_id integer,
postgres(#    subject_id integer
postgres(#  );
NOTICE:  CREATE TABLE / UNIQUE will create implicit index "new_books_id_key" for table "new_books"
CREATE TABLE
postgres=#
postgres=# INSERT INTO new_books
postgres-#              SELECT id, title, author_id, subject_id
postgres-#                     FROM books;
INSERT 0 8
postgres=#
postgres=# ALTER TABLE books RENAME TO old_books;
ALTER TABLE
postgres=#
postgres=# ALTER TABLE new_books RENAME TO books;
ALTER TABLE
postgres=#
postgres=# drop table books;
DROP TABLE
postgres=# drop table old_books;
DROP TABLE
postgres=#
postgres=#