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import psycopg2

Traceback (most recent call last):
  File "python_new_hire.sql", line 1, in <module>
    import psycopg2
ModuleNotFoundError: No module named 'psycopg2'

yum install python3-psycopg2

====================================================================================
 Package                  Architecture   Version               Repository      Size
====================================================================================
Installing:
 python3-psycopg2         x86_64         2.7.7-1.fc30          fedora         160 k
 
Transaction Summary
====================================================================================
Install  1 Package
 
Total download size: 160 k
Installed size: 593 k
Is this ok [y/N]: y
Downloading Packages:
python3-psycopg2-2.7.7-1.fc30.x86_64.rpm            364 kB/s | 160 kB     00:00    
------------------------------------------------------------------------------------
Total                                               167 kB/s | 160 kB     00:00     
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transaction
  Preparing        :                                                            1/1 
  Installing       : python3-psycopg2-2.7.7-1.fc30.x86_64                       1/1 
  Running scriptlet: python3-psycopg2-2.7.7-1.fc30.x86_64                       1/1 
  Verifying        : python3-psycopg2-2.7.7-1.fc30.x86_64                       1/1 
 
Installed:
  python3-psycopg2-2.7.7-1.fc30.x86_64                                              
 
Complete!

-- Environment settings for the script.
SET SESSION "videodb.table_name" = 'new_hire';
SET CLIENT_MIN_MESSAGES TO ERROR;
 
--  Verify table name.
SELECT current_setting('videodb.table_name');
 
-- ------------------------------------------------------------------
--  Conditionally drop table.
-- ------------------------------------------------------------------
DROP TABLE IF EXISTS new_hire CASCADE;
 
-- ------------------------------------------------------------------
--  Create table.
-- -------------------------------------------------------------------
CREATE TABLE new_hire
( new_hire_id  SERIAL
, first_name   VARCHAR(20)  NOT NULL
, middle_name  VARCHAR(20)
, last_name    VARCHAR(20)  NOT NULL
, hire_date    TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT CURRENT_TIMESTAMP
, PRIMARY KEY (new_hire_id));
 
-- Alter the sequence by restarting it at 1001.
ALTER SEQUENCE new_hire_new_hire_id_seq RESTART WITH 1001;
 
-- Display the table organization.
SELECT   tc.table_catalog || '.' || tc.constraint_name AS constraint_name
,        tc.table_catalog || '.' || tc.table_name AS table_name
,        kcu.column_name
,        ccu.table_catalog || '.' || ccu.table_name AS foreign_table_name
,        ccu.column_name AS foreign_column_name
FROM     information_schema.table_constraints AS tc JOIN information_schema.key_column_usage AS kcu
ON       tc.constraint_name = kcu.constraint_name
AND      tc.table_schema = kcu.table_schema JOIN information_schema.constraint_column_usage AS ccu
ON       ccu.constraint_name = tc.constraint_name
AND      ccu.table_schema = tc.table_schema
WHERE    tc.constraint_type = 'FOREIGN KEY'
AND      tc.table_name = current_setting('videodb.table_name')
ORDER BY 1;
 
SELECT c1.table_name
,      c1.ordinal_position
,      c1.column_name
,      CASE
         WHEN c1.is_nullable = 'NO' AND c2.column_name IS NOT NULL THEN 'PRIMARY KEY'
         WHEN c1.is_nullable = 'NO' AND c2.column_name IS NULL THEN 'NOT NULL'
       END AS is_nullable
,      CASE
         WHEN data_type = 'character varying' THEN
           data_type||'('||character_maximum_length||')'
         WHEN data_type = 'numeric' THEN
           CASE
             WHEN numeric_scale != 0 AND numeric_scale IS NOT NULL THEN
               data_type||'('||numeric_precision||','||numeric_scale||')'
             ELSE
               data_type||'('||numeric_precision||')'
             END
         ELSE
           data_type
        END AS data_type
FROM    information_schema.columns c1 LEFT JOIN
          (SELECT trim(regexp_matches(column_default,current_setting('videodb.table_name'))::text,'{}')||'_id' column_name
           FROM   information_schema.columns) c2
ON       c1.column_name = c2.column_name
WHERE    c1.table_name = current_setting('videodb.table_name')
ORDER BY c1.ordinal_position;
 
-- Display primary key and unique constraints.
SELECT constraint_name
,      lower(constraint_type) AS constraint_type
FROM   information_schema.table_constraints
WHERE  table_name = current_setting('videodb.table_name')
AND    constraint_type IN ('PRIMARY KEY','UNIQUE');
 
-- Insert two test records.
INSERT INTO new_hire
( first_name, middle_name, last_name, hire_date )
VALUES
 ('Malcolm','Jacob','Lewis','2018-2-14')
,('Henry',null,'Chabot','1990-07-31');

\i new_hire.sql

# Import the PostgreSQL connector library.
import psycopg2
 
try:
  # Open a connection to the database.
  connection = psycopg2.connect( user="student"
                               , password="student"
                               , port="5432"
                               , dbname="videodb")
 
  # Open a cursor.
  cursor = connection.cursor()
 
  # Assign a static query.
  query = "SELECT new_hire_id, first_name, last_name " \
          "FROM new_hire"
 
  # Parse and execute the query.
  cursor.execute(query)
 
  # Fetch all rows from a table.
  records = cursor.fetchall()
 
  # Read through and print the rows as tuples.
  for row in range(0, len(records)):
    print(records[row]) 
 
except (Exception, psycopg2.Error) as error :
  print("Error while fetching data from PostgreSQL", error)
 
finally:
  # Close the database connection.
  if (connection):
    cursor.close()
    connection.close()

python3 ./new_hire.py

(1001, 'Malcolm', 'Lewis')
(1002, 'Henry', 'Chabot')

\d account_list

ERROR:  structure of query does not match function result type
DETAIL:  Returned type information_schema.sql_identifier does not match expected type character varying in column 1.

RETURNS TABLE ( table_schema      information_schema.columns.table_schema%TYPE
              , table_name        information_schema.columns.table_name%TYPE
              , ordinal_position  information_schema.columns.ordinal_position%TYPE
              , column_name       information_schema.columns.column_name%TYPE
              , data_type         information_schema.columns.data_type%TYPE
              , is_nullable       information_schema.columns.is_nullable%TYPE ) AS

psql:describe_table.sql:34: NOTICE:  type reference information_schema.columns.table_schema%TYPE converted to information_schema.sql_identifier
psql:describe_table.sql:35: NOTICE:  type reference information_schema.columns.table_name%TYPE converted to information_schema.sql_identifier
psql:describe_table.sql:36: NOTICE:  type reference information_schema.columns.ordinal_position%TYPE converted to information_schema.cardinal_number
psql:describe_table.sql:37: NOTICE:  type reference information_schema.columns.column_name%TYPE converted to information_schema.sql_identifier
psql:describe_table.sql:38: NOTICE:  type reference information_schema.columns.data_type%TYPE converted to information_schema.character_data
psql:describe_table.sql:39: NOTICE:  type reference information_schema.columns.is_nullable%TYPE converted to information_schema.yes_or_no

SELECT attname
,      atttypid::regtype
FROM   pg_attribute
WHERE  attrelid = 'information_schema.columns'::regclass
AND    attname IN ('table_schema','table_name','ordinal_position','column_name','data_type','is_nullable')
ORDER  BY attnum;

     attname      |              atttypid
------------------+------------------------------------
 table_schema     | information_schema.sql_identifier
 table_name       | information_schema.sql_identifier
 ordinal_position | information_schema.cardinal_number
 column_name      | information_schema.sql_identifier
 is_nullable      | information_schema.yes_or_no
 data_type        | information_schema.character_data
(6 rows)

CREATE OR REPLACE
  FUNCTION describe_table (table_name_in  VARCHAR)
  RETURNS TABLE ( table_schema      information_schema.sql_identifier
                , table_name        information_schema.sql_identifier
                , ordinal_position  information_schema.cardinal_number
                , column_name       information_schema.sql_identifier
                , data_type         VARCHAR
                , is_nullable       information_schema.yes_or_no ) AS
$$
BEGIN
  RETURN QUERY
  SELECT   c.table_schema
  ,        c.table_name
  ,        c.ordinal_position
  ,        c.column_name
  ,        CASE
             WHEN c.character_maximum_length IS NOT NULL
             THEN CONCAT(c.data_type, '(', c.character_maximum_length, ')')
             ELSE
               CASE
                 WHEN c.data_type NOT IN ('date','timestamp','timestamp with time zone')
                 THEN CONCAT(c.data_type, '(', numeric_precision::text, ')')
                 ELSE c.data_type
               END
           END AS modified_type
  ,        c.is_nullable
  FROM     information_schema.columns c
  WHERE    c.table_schema NOT IN ('information_schema', 'pg_catalog')
  AND      c.table_name = table_name_in
  ORDER BY c.table_schema
  ,        c.table_name
  ,        c.ordinal_position;
END;
$$ LANGUAGE plpgsql;

SELECT * FROM describe_table('account_list');

 table_schema |  table_name  | ordinal_position |   column_name    |        data_type         | is_nullable
--------------+--------------+------------------+------------------+--------------------------+-------------
 public       | account_list |                1 | account_list_id  | integer(32)              | NO
 public       | account_list |                2 | account_number   | character varying(10)    | NO
 public       | account_list |                3 | consumed_date    | date                     | YES
 public       | account_list |                4 | consumed_by      | integer(32)              | YES
 public       | account_list |                5 | created_by       | integer(32)              | NO
 public       | account_list |                6 | creation_date    | timestamp with time zone | NO
 public       | account_list |                7 | last_updated_by  | integer(32)              | NO
 public       | account_list |                8 | last_update_date | timestamp with time zone | NO
(8 rows)

-- Drop the overloaded functions.
DROP FUNCTION IF EXISTS hello_world(), hello_world(whom VARCHAR);
 
-- Create the function.
CREATE FUNCTION hello_world()
RETURNS text AS
$$
DECLARE
  output  VARCHAR(20);
BEGIN
  /* Query the string into a local variable. */
  SELECT 'Hello World!' INTO output;
 
  /* Return the output text variable. */
  RETURN output;
END
$$ LANGUAGE plpgsql;
 
-- Create the function.
CREATE FUNCTION hello_world(whom VARCHAR)
RETURNS text AS
$$
DECLARE
  output  VARCHAR(20);
BEGIN
  /* Query the string into a local variable. */
  IF whom IS NULL OR LENGTH(whom) = 0 THEN
    SELECT 'Hello World!' INTO output;
  ELSE
    SELECT CONCAT('Hello ', whom, '!') INTO output;
  END IF;
 
 
  /* Return the output text variable. */
  RETURN output;
END
$$ LANGUAGE plpgsql;
 
-- Call the function.
SELECT hello_world();
SELECT hello_world(Null) AS output;
SELECT hello_world('') AS output;
SELECT hello_world('Harry') AS output;

    output
--------------
 Hello World!
(1 row)
 
    output
--------------
 Hello World!
(1 row)
 
    output
--------------
 Hello World!
(1 row)
 
    output
--------------
 Hello Harry!
(1 row)

Microsoft Windows [Version 10.0.19042.1466]
(c) Microsoft Corporation. All rights reserved.
 
C:\Users\username>

C:\Users\username>psql

'psql' is not recognized as an internal or external command, operable program or batch file.

set PATH=%PATH%;C:\Program Files\PostgreSQL\14\bin;

C:\Users\username>psql

psql: error: connection to server at "localhost" (::1), port 5432 failed: fe_sendauth: no password supplied

C:\Users\username>psql -U postgres

Password for user postgres:
psql (14.1)
WARNING: Console code page (437) differs from Windows code page (1252)
         8-bit characters might not work correctly. See psql reference
         page "Notes for Windows users" for details.
Type "help" for help.
 
postgres=#

chcp 1252

psql (14.2)
Type "help" for help.
 
postgres#

Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Command Processor

CREATE OR REPLACE 
  FUNCTION sales_tax( IN  amount  real
                    , OUT tax     real )
  AS $$
BEGIN
  /* Calculate the tax at 6%. */
  tax := amount * 0.06;
END;
$$ LANGUAGE plpgsql;

CREATE OR REPLACE 
  FUNCTION sales_tax( IN  amount  real
                    , OUT tax     real )
  RETURNS real AS
$$
BEGIN
  /* Calculate the tax at 6%. */
  tax := amount * 0.06;
END;
$$ LANGUAGE plpgsql;

SELECT 'Sales Tax ['|| sales_tax(200) ||']' AS "Return Value";

  Return Value  
----------------
 Sales Tax [12]
(1 row)

DO
$$
DECLARE
  /* Declare a local variable. */
  tax_paid  real := 0;
BEGIN
  /* Query the results into a local variable. */
  SELECT sales_tax(100) INTO tax_paid;
 
  /* Print the taxes paid. */
  RAISE NOTICE 'Tax Paid [%]',tax_paid;
END;
$$;

CREATE OR REPLACE
  FUNCTION sales_tax( IN  amount   real
                    , IN  tax_rate real )
  RETURNS real AS $$
DECLARE
  /* Declare a local variable. */
  tax real;
BEGIN
  /* Calculate the tax at 6%. */
  tax := amount * (tax_rate / 100);
 
  /* Return the tax. */
  RETURN tax;
END;
$$ LANGUAGE plpgsql;

CREATE OR REPLACE
  FUNCTION sales_tax( IN     amount   real
                    , IN     tax_rate real
                    , INOUT  state    VARCHAR(14)
                    , OUT    tax      real )
  RETURNS RECORD AS
$$
BEGIN
  /* Calculate the tax at 6%. */
  tax := amount * (tax_rate / 100);
END;
$$ LANGUAGE plpgsql;

SELECT 'Sales Tax ['|| sales_tax(100,8.25,'California') ||']' AS "Return Value";

         Return Value          
-------------------------------
 Sales Tax [(California,8.25)]
(1 row)

DO
$$
DECLARE
  /* Declare a local variable. */
  state     varchar(14) := 'California';
  tax_paid  real        := 0;
  result    RECORD;
BEGIN
  /* Query the results into a local variable. */
  SELECT sales_tax(100,8.25,state) INTO result;
 
  /* Print the taxes paid. */
  RAISE NOTICE 'Tax Paid [%]', result;
END;
$$;

NOTICE:  Tax Paid [("(California,8.25)")]

SELECT * FROM sales_tax(100,8.25,'California');

   state    | tax  
------------+------
 California | 8.25
(1 row)

DO
$$
DECLARE
  /* Declare a local variable. */
  state     varchar(14) := 'California';
  tax_paid  real        := 0;
BEGIN
  /* Query the results into a local variable. */
  SELECT * INTO state, tax_paid FROM sales_tax(100,8.25,state);
 
  /* Print the taxes paid. */
  RAISE NOTICE 'Tax Paid [%] [%]', state, tax_paid;
END;
$$;

NOTICE:  Tax Paid [California] [8.25]

CREATE OR REPLACE
  FUNCTION sales_tax( IN  subtotal REAL
                    , IN  tax_rate REAL
                    , IN  state    VARCHAR(14))
  RETURNS RECORD AS
$$
DECLARE
  /* Declare a local variable. */
  tax        REAL;
  tax_record RECORD;
BEGIN
  /* Calculate the tax at 6%. */
  tax := subtotal * (tax_rate / 100);
 
  /* Assign state to record. */
  SELECT state, tax INTO tax_record;
 
  /* Return the tax. */
  RETURN tax_record;
END;
$$ LANGUAGE plpgsql;

  SELECT state, tax INTO tax_record;

dnf -y install pgadmin4

mkdir -p /var/lib/pgadmin4 /var/lib/pgadmin4/sessions /var/lib/pgadmin4/storage /var/log/pgadmin4

chown -R apache:apache /var/lib/pgadmin4 /var/lib/pgadmin4/sessions /var/lib/pgadmin4/storage /var/log/pgadmin4

LOG_FILE = '/var/log/pgadmin4/pgadmin4.log'
SQLITE_PATH = '/var/lib/pgadmin4/pgadmin4.db'
SESSION_DB_PATH = '/var/lib/pgadmin4/sessions'
STORAGE_DIR = '/var/lib/pgadmin4/storage'

python3 /usr/lib/python3.7/site-packages/pgadmin4-web/setup.py

NOTE: Configuring authentication for SERVER mode.
 
Enter the email address and password to use for the initial pgAdmin user account:
 
Email address: admin@example.com   
Password: your_password
Retype password: your_password
pgAdmin 4 - Application Initialisation
======================================

firewall-cmd --permanent --add-service=http
firewall-cmd --reload

pgadmin/localhost/pgadmin4

ausearch -c 'httpd' --raw | audit2allow -M my-httpd
semodule -i my-httpd.pp

http://localhost/pgadmin4

DROP TABLE IF EXISTS CHARACTER;
CREATE TABLE CHARACTER
( character_id    SERIAL
, character_name  VARCHAR );

DROP TABLE IF EXISTS logger;
CREATE TABLE logger
( logger_id     SERIAL
, message_text  VARCHAR );

INSERT INTO CHARACTER
( character_name )
VALUES
('Harry Potter');

WITH cte AS
( SELECT 'Harry Potter' AS character_name
  UNION ALL
  SELECT 'Hermione Granger' AS character_name
  UNION ALL
  SELECT 'Ronald Weasily' AS character_name )
INSERT INTO CHARACTER
( character_name )
( SELECT character_name
  FROM   cte
  WHERE  NOT EXISTS
          (SELECT NULL
           FROM   CHARACTER c
           WHERE  c.character_name = cte.character_name));

SELECT * FROM CHARACTER;

 character_id |  character_name  
--------------+------------------
            1 | Harry Potter
            2 | Hermione Granger
            3 | Ronald Weasily
(3 rows)

CREATE OR REPLACE
  FUNCTION character_query (pattern VARCHAR)
  RETURNS TABLE ( character_id    INTEGER
                , character_text  VARCHAR ) AS
$$
BEGIN
  RETURN QUERY
  SELECT c.character_id
  ,      c.character_name
  FROM   CHARACTER c
  WHERE  c.character_name SIMILAR TO '%'||pattern||'%';
END;
$$ LANGUAGE plpgsql;

SELECT * FROM character_query('Hermione');

 character_id |  character_text  
--------------+------------------
            2 | Hermione Granger
(1 row)

CREATE OR REPLACE
  FUNCTION character_query (pattern VARCHAR)
  RETURNS TABLE ( character_id    INTEGER
                , character_text  VARCHAR ) AS
$$
BEGIN
  INSERT INTO logger
  ( message_text )
  VALUES
  ( pattern );
 
  RETURN QUERY
  SELECT c.character_id
  ,      c.character_name
  FROM   CHARACTER c
  WHERE  c.character_name SIMILAR TO '%'||pattern||'%';
END;
$$ LANGUAGE plpgsql;

SELECT * FROM character_query('Ron');

SELECT * FROM logger;

 logger_id | message_text 
-----------+--------------
         1 | Hermione
(1 row)

SELECT row_to_json(
 (SELECT ROW
  FROM (SELECT item_id
        ,      item_barcode
        ,      item_type
        ,      item_title
        ,      item_subtitle
        ,      item_rating
        ,      item_release_date
        ,      created_by
        ,      creation_date::DATE
        ,      last_updated_by
        ,      last_update_date::DATE) ROW)) AS DATA
        FROM   item;

{"item_id":1001,"item_barcode":"9736-05640-4","item_type":1016,"item_title":"The Hunt for Red October","item_subtitle":"Special Collector's Edition","item_rating":"PG","item_release_date":"1990-03-02","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1002,"item_barcode":"24543-02392","item_type":1016,"item_title":"Star Wars I","item_subtitle":"Phantom Menace","item_rating":"PG","item_release_date":"1999-05-04","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1003,"item_barcode":"24543-5615","item_type":1015,"item_title":"Star Wars II","item_subtitle":"Attack of the Clones","item_rating":"PG","item_release_date":"2002-05-16","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1004,"item_barcode":"24543-05539","item_type":1016,"item_title":"Star Wars II","item_subtitle":"Attack of the Clones","item_rating":"PG","item_release_date":"2002-05-16","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1005,"item_barcode":"24543-20309","item_type":1016,"item_title":"Star Wars III","item_subtitle":"Revenge of the Sith","item_rating":"PG13","item_release_date":"2005-05-19","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1006,"item_barcode":"86936-70380","item_type":1016,"item_title":"The Chronicles of Narnia","item_subtitle":"The Lion, the Witch and the Wardrobe","item_rating":"PG","item_release_date":"2002-05-16","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1007,"item_barcode":"91493-06475","item_type":1019,"item_title":"RoboCop","item_subtitle":"","item_rating":"Mature","item_release_date":"2003-07-24","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1008,"item_barcode":"93155-11810","item_type":1019,"item_title":"Pirates of the Caribbean","item_subtitle":"","item_rating":"Teen","item_release_date":"2003-06-30","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1009,"item_barcode":"12725-00173","item_type":1019,"item_title":"The Chronicles of Narnia","item_subtitle":"The Lion, the Witch and the Wardrobe","item_rating":"Everyone","item_release_date":"2003-06-30","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1010,"item_barcode":"45496-96128","item_type":1017,"item_title":"MarioKart","item_subtitle":"Double Dash","item_rating":"Everyone","item_release_date":"2003-11-17","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1011,"item_barcode":"08888-32214","item_type":1018,"item_title":"Splinter Cell","item_subtitle":"Chaos Theory","item_rating":"Teen","item_release_date":"2003-04-08","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1012,"item_barcode":"14633-14821","item_type":1018,"item_title":"Need for Speed","item_subtitle":"Most Wanted","item_rating":"Everyone","item_release_date":"2004-11-15","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1013,"item_barcode":"10425-29944","item_type":1019,"item_title":"The DaVinci Code","item_subtitle":"","item_rating":"Teen","item_release_date":"2006-05-19","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1014,"item_barcode":"52919-52057","item_type":1019,"item_title":"Cars","item_subtitle":"","item_rating":"Everyone","item_release_date":"2006-04-28","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1015,"item_barcode":"9689-80547-3","item_type":1020,"item_title":"Beau Geste","item_subtitle":"","item_rating":"PG","item_release_date":"1992-03-01","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1016,"item_barcode":"53939-64103","item_type":1020,"item_title":"I Remember Mama","item_subtitle":"","item_rating":"NR","item_release_date":"1998-01-05","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1017,"item_barcode":"24543-01292","item_type":1020,"item_title":"Tora! Tora! Tora!","item_subtitle":"The Attack on Pearl Harbor","item_rating":"G","item_release_date":"1999-11-02","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1018,"item_barcode":"43396-60047","item_type":1020,"item_title":"A Man for All Seasons","item_subtitle":"","item_rating":"G","item_release_date":"1994-06-28","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1019,"item_barcode":"43396-70603","item_type":1020,"item_title":"Hook","item_subtitle":"","item_rating":"PG","item_release_date":"1991-12-11","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1020,"item_barcode":"85391-13213","item_type":1020,"item_title":"Around the World in 80 Days","item_subtitle":"","item_rating":"G","item_release_date":"1992-12-04","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}
{"item_id":1021,"item_barcode":"85391-10843","item_type":1020,"item_title":"Camelot","item_subtitle":"","item_rating":"G","item_release_date":"1998-05-15","created_by":1001,"creation_date":"2019-12-13","last_updated_by":1001,"last_update_date":"2019-12-13"}

COPY
(SELECT row_to_json(
  (SELECT ROW
   FROM (SELECT item_id
         ,      item_barcode
         ,      item_type
         ,      item_title
         ,      item_subtitle
         ,      item_rating
         ,      item_release_date
         ,      created_by
         ,      creation_date::DATE
         ,      last_updated_by
         ,      last_update_date::DATE) ROW)) AS DATA
         FROM   item) TO '/tmp/sample.json';

ERROR:  must be superuser or a member of the pg_write_server_files role to COPY to a file
HINT:  Anyone can COPY to stdout or from stdin. psql's \copy command also works for anyone.

GRANT pg_write_server_files TO student;

GRANT CREATE ON DATABASE videodb TO student;

CREATE SCHEMA app;

SELECT   * 
FROM     pg_catalog.pg_namespace
ORDER BY nspname;

      nspname       | nspowner |               nspacl                
--------------------+----------+-------------------------------------
 app                |    16390 | 
 information_schema |       10 | {postgres=UC/postgres,=U/postgres}
 pg_catalog         |       10 | {postgres=UC/postgres,=U/postgres}
 pg_temp_1          |       10 | 
 pg_toast           |       10 | 
 pg_toast_temp_1    |       10 | 
 public             |       10 | {postgres=UC/postgres,=UC/postgres}
(7 rows)

CREATE TABLE app.revision_history
( revision_history_id serial
, session_id          VARCHAR
, TABLE_NAME          VARCHAR
, revision_id         INTEGER );

\d revision_history

Did not find any relation named "revision_history".

show search_path;

   search_path   
-----------------
 "$user", public
(1 row)

SET search_path TO app, "$user", public;

\d revision_history

                                                  Table "app.revision_history"
       Column        |       Type        | Collation | Nullable |                            Default                            
---------------------+-------------------+-----------+----------+---------------------------------------------------------------
 revision_history_id | integer           |           | not null | nextval('revision_history_revision_history_id_seq'::regclass)
 session_id          | character varying |           |          | 
 table_name          | character varying |           |          | 
 revision_id         | integer           |           |          |