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rpm -Uvh https://yum.postgresql.org/11/fedora/fedora-30-x86_64/pgdg-fedora-repo-latest.noarch.rpm

dnf install postgresql11-server

/usr/pgsql-11/bin/postgresql-11-setup initdb

Initializing database ... OK

drwx------. 5 postgres postgres  4096 Aug 19 02:45 base
drwx------. 2 postgres postgres  4096 Aug 19 02:45 global
drwx------. 2 postgres postgres  4096 Aug 19 02:45 log
drwx------. 2 postgres postgres  4096 Aug 19 02:45 pg_commit_ts
drwx------. 2 postgres postgres  4096 Aug 19 02:45 pg_dynshmem
-rw-------. 1 postgres postgres  4269 Aug 19 02:45 pg_hba.conf
-rw-------. 1 postgres postgres  1636 Aug 19 02:45 pg_ident.conf
drwx------. 4 postgres postgres  4096 Aug 19 02:45 pg_logical
drwx------. 4 postgres postgres  4096 Aug 19 02:45 pg_multixact
drwx------. 2 postgres postgres  4096 Aug 19 02:45 pg_notify
drwx------. 2 postgres postgres  4096 Aug 19 02:45 pg_replslot
drwx------. 2 postgres postgres  4096 Aug 19 02:45 pg_serial
drwx------. 2 postgres postgres  4096 Aug 19 02:45 pg_snapshots
drwx------. 2 postgres postgres  4096 Aug 19 02:45 pg_stat
drwx------. 2 postgres postgres  4096 Aug 19 02:45 pg_stat_tmp
drwx------. 2 postgres postgres  4096 Aug 19 02:45 pg_subtrans
drwx------. 2 postgres postgres  4096 Aug 19 02:45 pg_tblspc
drwx------. 2 postgres postgres  4096 Aug 19 02:45 pg_twophase
-rw-------. 1 postgres postgres     3 Aug 19 02:45 PG_VERSION
drwx------. 3 postgres postgres  4096 Aug 19 02:45 pg_wal
drwx------. 2 postgres postgres  4096 Aug 19 02:45 pg_xact
-rw-------. 1 postgres postgres    88 Aug 19 02:45 postgresql.auto.conf
-rw-------. 1 postgres postgres 23895 Aug 19 02:45 postgresql.conf

systemctl enable postgresql-11.service
systemctl start postgresql-11.service

su - postgres -c "psql"

psql: /usr/pgsql-11/lib/libpq.so.5: no version information available (required by psql)
psql: /usr/pgsql-11/lib/libpq.so.5: no version information available (required by psql)
psql (11.4, server 11.5)
Type "help" for help.
 
postgres=#

[ -f /etc/profile ] && source /etc/profile
PGDATA=/var/lib/pgsql/11/data
export PGDATA
# If you want to customize your settings,
# Use the file below. This is not overridden
# by the RPMS.
[ -f /var/lib/pgsql/.pgsql_profile ] && source /var/lib/pgsql/.pgsql_profile

export set LD_LIBRARY_PATH=/usr/lib64 needle < /dev/null

psql -U postgres

psql (11.4, server 11.5)
Type "help" for help.
 
postgres=#

su - postgres -c "psql"

SELECT 'Hello World!';

SELECT 'Hello ['||current_user||']!';

\i helloworld.sql

   ?column?   
--------------
 Hello World!

\include hellowhom.sql

     ?column?     
------------------
 Hello [student]!

CREATE TABLE auto
( id           INT UNSIGNED PRIMARY KEY AUTO_INCREMENT
, text_field   VARCHAR(30)  NOT NULL
) ENGINE=InnoDB AUTO_INCREMENT=1001 DEFAULT CHARSET=utf8;

CREATE TABLE auto
( auto_id     NUMBER GENERATED BY DEFAULT AS IDENTITY (START WITH 1001)
, text_field  VARCHAR2(30)
, CONSTRAINT  auto_pk PRIMARY KEY (auto_id));

CREATE TABLE auto
( id          SERIAL      CONSTRAINT auto_pk PRIMARY KEY
, text_field  VARCHAR(30));
 
ALTER SEQUENCE auto_id_seq RESTART WITH 1001;

\d+ auto

                                                      Table "public.auto"
   Column   |         Type          |                     Modifiers                     | Storage  | Stats target | Description 
------------+-----------------------+---------------------------------------------------+----------+--------------+-------------
 id         | integer               | not null default nextval('auto_id_seq'::regclass) | plain    |              | 
 text_field | character varying(30) |                                                   | extended |              | 
Indexes:
    "auto_pk" PRIMARY KEY, btree (id)
Has OIDs: no

CREATE TYPE address_type AS
( street_address  VARCHAR
, city            VARCHAR
, state           VARCHAR
, zip_code        VARCHAR );

CREATE TABLE address
( address_id      SERIAL
, address_struct  ADDRESS_TYPE );

-- Insert the first row.
INSERT INTO address
( address_struct )
VALUES
(('52 Hubble Street','Lexington','KY','40511-1225'));
 
-- Insert the second row.
INSERT INTO address
( address_struct )
VALUES
(('54 Hubble Street','Lexington','KY','40511-1225'));

SELECT * FROM address;

 address_id |                address_struct
------------+----------------------------------------------
          1 | ("52 Hubble Street",Lexington,KY,40511-1225)
          2 | ("54 Hubble Street",Lexington,KY,40511-1225)
(2 rows)

SELECT   address_id
,       (address_struct).street_address
,       (address_struct).city
,       (address_struct).state
,       (address_struct).zip_code
FROM     address;

 address_id |  street_address  |   city    | state |  zip_code
------------+------------------+-----------+-------+------------
          1 | 52 Hubble Street | Lexington | KY    | 40511-1225
          2 | 54 Hubble Street | Lexington | KY    | 40511-1225
(2 rows)

/* Create a customer table. */
CREATE TABLE customer
( customer_id     SERIAL CONSTRAINT customer_pk PRIMARY KEY
, first_name      VARCHAR(20)
, last_name       VARCHAR(20));
 
/* Create an address table. */
CREATE TABLE address
( address_id      SERIAL CONSTRAINT address_pk PRIMARY KEY
, customer_id     INTEGER
, street_address  VARCHAR(40)
, city            VARCHAR(30)
, state           VARCHAR(8)
, zip_code        VARCHAR(10));

/* Insert into customer table. */
INSERT INTO customer
( first_name, last_name ) 
VALUES
('F. Scott','Fitzgerald');
 
/* Insert into address table. */
INSERT INTO address
( customer_id
, street_address
, city
, state
, zip_code )
VALUES
((SELECT   customer_id
  FROM     customer
  WHERE    first_name = 'F. Scott'
  AND      last_name = 'Fitzgerald')
,'599 Summit Avenue'
,'St. Paul'
,'Minnesota'
,'55102');

DO $$
DECLARE lv_customer_id INTEGER;
BEGIN
  /* Insert into customer table. */
  INSERT INTO customer
  ( first_name, last_name ) 
  VALUES
  ('Madeleine','Smith') 
  RETURNING customer_id INTO lv_customer_id;
 
  /* Insert into address table. */
  INSERT INTO address
  ( customer_id
  , street_address
  , city
  , state
  , zip_code )
  VALUES
  ( lv_customer_id
  ,'7 Blythswood Square'
  ,'Glasgow'
  ,'Scotland'
  ,'G2 4BG');
 
  /* Manage any exceptions. */
  EXCEPTION
    WHEN OTHERS THEN
      RAISE NOTICE '% %', SQLERRM, SQLSTATE;
END$$;

SELECT   *
FROM     customer c INNER JOIN address a
ON       c.customer_id = a.customer_id;

 customer_id | first_name | last_name  | address_id | customer_id |   street_address    |   city   |   state   | zip_code
-------------+------------+------------+------------+-------------+---------------------+----------+-----------+----------
           1 | F. Scott   | Fitzgerald |          1 |           1 | 599 Summit Avenue   | St. Paul | Minnesota | 55102
           2 | Madeleine  | Smith      |          2 |           2 | 7 Blythswood Square | Glasgow  | Scotland  | G2 4BG
(2 rows)

DROP FUNCTION IF EXISTS full_name
( IN pv_first_name  text
, IN pv_middle_name text
, IN pv_full_name   text);
 
CREATE FUNCTION full_name
( IN  pv_first_name  text
, IN  pv_middle_name text
, IN  pv_last_name   text
, OUT pv_full_name   text) AS
   'SELECT  pv_first_name
    ||      CASE
              WHEN pv_middle_name IS NOT NULL THEN '' '' || pv_middle_name || '' ''
              ELSE '' ''
            END
    ||      pv_last_name'
    LANGUAGE SQL;

DROP FUNCTION IF EXISTS full_name
( IN text
, IN text
, IN text);
 
CREATE FUNCTION full_name
( IN text
, IN text
, IN text
, OUT text) AS
   'SELECT  $1
    ||      CASE
              WHEN $2 IS NOT NULL THEN '' '' || $2 || '' ''
              ELSE '' ''
            END
    ||      $3'
    LANGUAGE SQL;

CREATE FUNCTION full_name
( IN  pv_first_name   text
, IN  pv_middle_name  text
, IN  pv_last_name    text) RETURNS text AS
$$
DECLARE
  lv_output text;
BEGIN
  IF pv_middle_name IS NULL THEN
    lv_output = CONCAT(pv_first_name, N' ', pv_last_name);
  ELSE
    lv_output = CONCAT(pv_first_name, N' ', pv_middle_name, N' ', pv_first_name);
  END IF;
  RETURN lv_output;
END
$$
LANGUAGE plpgsql IMMUTABLE;

SELECT full_name('Henry',NULL,'Pym') AS "Ant-Man"
UNION ALL
SELECT full_name('Henry','''Hank''','Pym') AS "Ant-Man";

Ant-Man
text
----------------
Henry Pym
Henry 'Hank' Pym

yum localinstall http://yum.postgresql.org/9.3/fedora/fedora-20-x86_64/pgdg-fedora93-9.3-1.noarch.rpm

Loaded plugins: langpacks, refresh-packagekit
pgdg-fedora93-9.3-1.noarch.rpm                              | 5.1 kB  00:00     
Examining /var/tmp/yum-root-2EPf_J/pgdg-fedora93-9.3-1.noarch.rpm: pgdg-fedora93-9.3-1.noarch
Marking /var/tmp/yum-root-2EPf_J/pgdg-fedora93-9.3-1.noarch.rpm to be installed
Resolving Dependencies
--> Running transaction check
---> Package pgdg-fedora93.noarch 0:9.3-1 will be installed
--> Finished Dependency Resolution
 
Dependencies Resolved
 
================================================================================
 Package           Arch       Version     Repository                       Size
================================================================================
Installing:
 pgdg-fedora93     noarch     9.3-1       /pgdg-fedora93-9.3-1.noarch     2.1 k
 
Transaction Summary
================================================================================
Install  1 Package
 
Total size: 2.1 k
Installed size: 2.1 k
Is this ok [y/d/N]: y
Downloading packages:
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction (shutdown inhibited)
  Installing : pgdg-fedora93-9.3-1.noarch                                   1/1 
  Verifying  : pgdg-fedora93-9.3-1.noarch                                   1/1 
 
Installed:
  pgdg-fedora93.noarch 0:9.3-1                                                  
 
Complete!

yum install postgresql93-server

Loaded plugins: langpacks, refresh-packagekit
pgdg93                                                      | 3.6 kB  00:00     
(1/2): pgdg93/20/x86_64/group_gz                            |  332 B  00:00     
(2/2): pgdg93/20/x86_64/primary_db                          |  84 kB  00:00     
Resolving Dependencies
--> Running transaction check
---> Package postgresql93-server.x86_64 0:9.3.5-1PGDG.f20 will be installed
--> Processing Dependency: postgresql93-libs(x86-64) = 9.3.5-1PGDG.f20 for package: postgresql93-server-9.3.5-1PGDG.f20.x86_64
--> Processing Dependency: postgresql93(x86-64) = 9.3.5-1PGDG.f20 for package: postgresql93-server-9.3.5-1PGDG.f20.x86_64
--> Processing Dependency: postgresql93 = 9.3.5-1PGDG.f20 for package: postgresql93-server-9.3.5-1PGDG.f20.x86_64
--> Processing Dependency: libpq.so.5()(64bit) for package: postgresql93-server-9.3.5-1PGDG.f20.x86_64
--> Running transaction check
---> Package postgresql93.x86_64 0:9.3.5-1PGDG.f20 will be installed
---> Package postgresql93-libs.x86_64 0:9.3.5-1PGDG.f20 will be installed
--> Finished Dependency Resolution
 
Dependencies Resolved
 
================================================================================
 Package                  Arch        Version                 Repository   Size
================================================================================
Installing:
 postgresql93-server      x86_64      9.3.5-1PGDG.f20         pgdg93      3.6 M
Installing for dependencies:
 postgresql93             x86_64      9.3.5-1PGDG.f20         pgdg93      1.0 M
 postgresql93-libs        x86_64      9.3.5-1PGDG.f20         pgdg93      203 k
 
Transaction Summary
================================================================================
Install  1 Package (+2 Dependent packages)
 
Total download size: 4.8 M
Installed size: 22 M
Is this ok [y/d/N]: y
Downloading packages:
(1/3): postgresql93-libs-9.3.5-1PGDG.f20.x86_64.rpm         | 203 kB  00:00     
(2/3): postgresql93-9.3.5-1PGDG.f20.x86_64.rpm              | 1.0 MB  00:01     
(3/3): postgresql93-server-9.3.5-1PGDG.f20.x86_64.rpm       | 3.6 MB  00:02     
--------------------------------------------------------------------------------
Total                                              1.6 MB/s | 4.8 MB  00:02     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction (shutdown inhibited)
  Installing : postgresql93-libs-9.3.5-1PGDG.f20.x86_64                     1/3 
  Installing : postgresql93-9.3.5-1PGDG.f20.x86_64                          2/3 
  Installing : postgresql93-server-9.3.5-1PGDG.f20.x86_64                   3/3 
  Verifying  : postgresql93-server-9.3.5-1PGDG.f20.x86_64                   1/3 
  Verifying  : postgresql93-9.3.5-1PGDG.f20.x86_64                          2/3 
  Verifying  : postgresql93-libs-9.3.5-1PGDG.f20.x86_64                     3/3 
 
Installed:
  postgresql93-server.x86_64 0:9.3.5-1PGDG.f20                                  
 
Dependency Installed:
  postgresql93.x86_64 0:9.3.5-1PGDG.f20                                         
  postgresql93-libs.x86_64 0:9.3.5-1PGDG.f20                                    
 
Complete!

rpm -qa | grep postgres

postgresql93-9.3.5-1PGDG.f20.x86_64
postgresql93-server-9.3.5-1PGDG.f20.x86_64
postgresql93-libs-9.3.5-1PGDG.f20.x86_64

whoami

root

su - postgres

postgres

psql

postgres=# SELECT setting as "Data Location"
postgres-# FROM   pg_settings
postgres-# WHERE  name = 'data_directory';

      Data Location      
-------------------------
 /var/lib/pgsql/9.3/data
(1 row)

C:\Data\PostgreSQL\env

COPY CON postgresqlenv.bat
SET PATH=%PATH%;C:\Program Files\PostgreSQL\9.3\bin;.
^Z

C:\> postgresql.bat

C:\> psql -d postgres -U postgres

C:\> psql -d postgres -U postgres
 Password for user postgres:
psql (9.3.3)
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=# SELECT 'Hello World!';

   ?COLUMN?
--------------
 Hello World!
(1 ROW)

postgres=# SELECT 'Hello World!' AS "String Literal";

 String Literal
----------------
 Hello World!
(1 ROW)

postgres=# help
You are USING psql, the command-line interface TO PostgreSQL.
TYPE:  \copyright FOR distribution terms
       \h FOR help WITH SQL commands
       \? FOR help WITH psql commands
       \g OR terminate WITH semicolon TO EXECUTE query
       \q TO quit

postgres=# \q

\HELP

Available help:
  ABORT                            CLUSTER                          DEALLOCATE                       END
  ALTER AGGREGATE                  COMMENT                          DECLARE                          EXECUTE
  ALTER COLLATION                  COMMIT                           DELETE                           EXPLAIN
  ALTER CONVERSION                 COMMIT PREPARED                  DISCARD                          FETCH
  ALTER DATABASE                   COPY                             DO                               GRANT
  ALTER DEFAULT PRIVILEGES         CREATE AGGREGATE                 DROP AGGREGATE                   INSERT
  ALTER DOMAIN                     CREATE CAST                      DROP CAST                        LISTEN
  ALTER EVENT TRIGGER              CREATE COLLATION                 DROP COLLATION                   LOAD
  ALTER EXTENSION                  CREATE CONVERSION                DROP CONVERSION                  LOCK
  ALTER FOREIGN DATA WRAPPER       CREATE DATABASE                  DROP DATABASE                    MOVE
  ALTER FOREIGN TABLE              CREATE DOMAIN                    DROP DOMAIN                      NOTIFY
  ALTER FUNCTION                   CREATE EVENT TRIGGER             DROP EVENT TRIGGER               PREPARE
  ALTER GROUP                      CREATE EXTENSION                 DROP EXTENSION                   PREPARE TRANSACTION
  ALTER INDEX                      CREATE FOREIGN DATA WRAPPER      DROP FOREIGN DATA WRAPPER        REASSIGN OWNED
  ALTER LANGUAGE                   CREATE FOREIGN TABLE             DROP FOREIGN TABLE               REFRESH MATERIALIZED VIEW
  ALTER LARGE OBJECT               CREATE FUNCTION                  DROP FUNCTION                    REINDEX
  ALTER MATERIALIZED VIEW          CREATE GROUP                     DROP GROUP                       RELEASE SAVEPOINT
  ALTER OPERATOR                   CREATE INDEX                     DROP INDEX                       RESET
  ALTER OPERATOR CLASS             CREATE LANGUAGE                  DROP LANGUAGE                    REVOKE
  ALTER OPERATOR FAMILY            CREATE MATERIALIZED VIEW         DROP MATERIALIZED VIEW           ROLLBACK
  ALTER ROLE                       CREATE OPERATOR                  DROP OPERATOR                    ROLLBACK PREPARED
  ALTER RULE                       CREATE OPERATOR CLASS            DROP OPERATOR CLASS              ROLLBACK TO SAVEPOINT
  ALTER OPERATOR                   CREATE INDEX                     DROP INDEX                       RESET
  ALTER OPERATOR CLASS             CREATE LANGUAGE                  DROP LANGUAGE                    REVOKE
  ALTER OPERATOR FAMILY            CREATE MATERIALIZED VIEW         DROP MATERIALIZED VIEW           ROLLBACK
  ALTER ROLE                       CREATE OPERATOR                  DROP OPERATOR                    ROLLBACK PREPARED
  ALTER RULE                       CREATE OPERATOR CLASS            DROP OPERATOR CLASS              ROLLBACK TO SAVEPOINT
  ALTER SCHEMA                     CREATE OPERATOR FAMILY           DROP OPERATOR FAMILY             SAVEPOINT
  ALTER SEQUENCE                   CREATE ROLE                      DROP OWNED                       SECURITY LABEL
  ALTER SERVER                     CREATE RULE                      DROP ROLE                        SELECT
  ALTER TABLE                      CREATE SCHEMA                    DROP RULE                        SELECT INTO
  ALTER TABLESPACE                 CREATE SEQUENCE                  DROP SCHEMA                      SET
  ALTER TEXT SEARCH CONFIGURATION  CREATE SERVER                    DROP SEQUENCE                    SET CONSTRAINTS
  ALTER TEXT SEARCH DICTIONARY     CREATE TABLE                     DROP SERVER                      SET ROLE
  ALTER TEXT SEARCH PARSER         CREATE TABLE AS                  DROP TABLE                       SET SESSION AUTHORIZATION
  ALTER TEXT SEARCH TEMPLATE       CREATE TABLESPACE                DROP TABLESPACE                  SET TRANSACTION
  ALTER TRIGGER                    CREATE TEXT SEARCH CONFIGURATION DROP TEXT SEARCH CONFIGURATION   SHOW
  ALTER TYPE                       CREATE TEXT SEARCH DICTIONARY    DROP TEXT SEARCH DICTIONARY      START TRANSACTION
  ALTER USER                       CREATE TEXT SEARCH PARSER        DROP TEXT SEARCH PARSER          TABLE
  ALTER USER MAPPING               CREATE TEXT SEARCH TEMPLATE      DROP TEXT SEARCH TEMPLATE        TRUNCATE
  ALTER VIEW                       CREATE TRIGGER                   DROP TRIGGER                     UNLISTEN
  ANALYZE                          CREATE TYPE                      DROP TYPE                        UPDATE
  BEGIN                            CREATE USER                      DROP USER                        VACUUM
  CHECKPOINT                       CREATE USER MAPPING              DROP USER MAPPING                VALUES
  CLOSE                            CREATE VIEW                      DROP VIEW                        WITH

\?

General
  \copyright             show PostgreSQL usage and distribution terms
  \g [FILE] or ;         execute query (and send results to file or |pipe)
  \gset [PREFIX]         execute query and store results in psql variables
  \h [NAME]              help on syntax of SQL commands, * for all commands
  \q                     quit psql
  \watch [SEC]           execute query every SEC seconds
 
Query Buffer
  \e [FILE] [LINE]       edit the query buffer (or file) with external editor
  \ef [FUNCNAME [LINE]]  edit function definition with external editor
  \p                     show the contents of the query buffer
  \r                     reset (clear) the query buffer
  \s [FILE]              display history or save it to file
  \w FILE                write query buffer to file
 
Input/Output
  \copy ...              perform SQL COPY with data stream to the client host
  \echo [STRING]         write string to standard output
  \i FILE                execute commands from file
  \ir FILE               as \i, but relative to location of current script
  \o [FILE]              send all query results to file or |pipe
  \qecho [STRING]        write string to query output stream (see \o)
 
Informational
  (options: S = show system objects, + = additional detail)
  \d[S+]                 list tables, views, and sequences
  \d[S+]  NAME           describe table, view, sequence, or index
  \da[S]  [PATTERN]      list aggregates
  \db[+]  [PATTERN]      list tablespaces
  \dc[S+] [PATTERN]      list conversions
  \dC[+]  [PATTERN]      list casts
  \dd[S]  [PATTERN]      show object descriptions not displayed elsewhere
  \ddp    [PATTERN]      list default privileges
  \dD[S+] [PATTERN]      list domains
  \det[+] [PATTERN]      list foreign tables
  \des[+] [PATTERN]      list foreign servers
  \deu[+] [PATTERN]      list user mappings
  \dew[+] [PATTERN]      list foreign-data wrappers
  \df[antw][S+] [PATRN]  list [only agg/normal/trigger/window] functions
  \dF[+]  [PATTERN]      list text search configurations
  \dFd[+] [PATTERN]      list text search dictionaries
  \dFp[+] [PATTERN]      list text search parsers
  \dFt[+] [PATTERN]      list text search templates
  \dg[+]  [PATTERN]      list roles
  \di[S+] [PATTERN]      list indexes
  \dl                    list large objects, same as \lo_list
  \dL[S+] [PATTERN]      list procedural languages
  \dm[S+] [PATTERN]      list materialized views
  \dn[S+] [PATTERN]      list schemas
  \do[S]  [PATTERN]      list operators
  \dO[S+] [PATTERN]      list collations
  \dp     [PATTERN]      list table, view, and sequence access privileges
  \drds [PATRN1 [PATRN2]] list per-database role settings
  \ds[S+] [PATTERN]      list sequences
  \dt[S+] [PATTERN]      list tables
  \dT[S+] [PATTERN]      list data types
  \du[+]  [PATTERN]      list roles
  \dv[S+] [PATTERN]      list views
  \dE[S+] [PATTERN]      list foreign tables
  \dx[+]  [PATTERN]      list extensions
  \dy     [PATTERN]      list event triggers
  \l[+]   [PATTERN]      list databases
  \sf[+] FUNCNAME        show a function's definition
  \z      [PATTERN]      same as \dp
 
Formatting
  \a                     toggle between unaligned and aligned output mode
  \C [STRING]            set table title, or unset if none
  \f [STRING]            show or set field separator for unaligned query output
  \H                     toggle HTML output mode (currently off)
  \pset NAME [VALUE]     set table output option
                         (NAME := {format|border|expanded|fieldsep|fieldsep_zero|footer|null|
                         numericlocale|recordsep|recordsep_zero|tuples_only|title|tableattr|pager})
  \t [on|off]            show only rows (currently off)
  \T [STRING]            set HTML <table> tag attributes, or unset if none
  \x [on|off|auto]       toggle expanded output (currently off)
 
Connection
  \c[onnect] {[DBNAME|- USER|- HOST|- PORT|-] | conninfo}
                         connect to new database (currently "studentdb")
  \encoding [ENCODING]   show or set client encoding
  \password [USERNAME]   securely change the password for a user
  \conninfo              display information about current connection
 
Operating System
  \cd [DIR]              change the current working directory
  \setenv NAME [VALUE]   set or unset environment variable
  \timing [on|off]       toggle timing of commands (currently off)
  \! [COMMAND]           execute command in shell or start interactive shell
 
Variables
  \prompt [TEXT] NAME    prompt user to set internal variable
  \set [NAME [VALUE]]    set internal variable, or list all if no parameters
  \unset NAME            unset (delete) internal variable
 
Large Objects
  \lo_export LOBOID FILE
  \lo_import FILE [COMMENT]
  \lo_list
  \lo_unlink LOBOID      large object operations