[oracle@Tesdb ~]$ systemctl status postgresql-15
● postgresql-15.service - PostgreSQL 15 database server
Loaded: loaded (/usr/lib/systemd/system/postgresql-15.service; enabled; vendor preset: disabled)
Active: active (running) since Thu 2024-02-01 17:45:15 +03; 3 days ago
Docs: https://www.postgresql.org/docs/15/static/
Process: 33491 ExecStartPre=/usr/pgsql-15/bin/postgresql-15-check-db-dir ${PGDATA} (code=exited, status=0/SUCCESS)
Main PID: 33500 (postmaster)
CGroup: /system.slice/postgresql-15.service
├─33500 /usr/pgsql-15/bin/postmaster -D /var/lib/pgsql/15/data/
├─33503 postgres: logger
├─33505 postgres: checkpointer
├─33506 postgres: background writer
├─33508 postgres: walwriter
├─33509 postgres: autovacuum launcher
├─33510 postgres: logical replication launcher
├─33541 postgres: postgres Tesdb [local] idle
├─65961 postgres: postgres Tesdb 172.16.162.240(61004) idle
├─69716 postgres: postgres Tesdb 172.16.162.240(63935) idle
├─69816 postgres: postgres Tesdb 172.16.162.240(64108) idle
├─71388 postgres: postgres postgres 10.28.68.209(49286) idle
├─71411 postgres: postgres Tesdb 172.16.162.240(49191) idle
└─71552 postgres: postgres postgres 10.28.68.215(44922) idle
[oracle@Tesdb ~]$
[oracle@Tesdb ~]$ sudo -i -u postgres
-bash-4.2$
-bash-4.2$
-bash-4.2$ id
uid=26(postgres) gid=26(postgres) groups=26(postgres)
[oracle@Tesdb ~]$ sudo -i -u postgres
-bash-4.2$
postgres-# \du
List of roles
Role name | Attributes | Member of
-----------+------------------------------------------------------------+-----------
postgres | Superuser, Create role, Create DB, Replication, Bypass RLS | {}
postgres-# \c Tesdb
You are now connected to database "Tesdb" as user "postgres".
Tesdb-#
Tesdb-#
Tesdb-#
Tesdb-# \l
List of databases
Name | Owner | Encoding | Collate | Ctype | ICU Locale | Locale Provider | Access privileges
-----------+----------+----------+-------------+-------------+------------+-----------------+-----------------------
Tesdb | postgres | UTF8 | en_US.UTF-8 | en_US.UTF-8 | | libc |
postgres | postgres | UTF8 | en_US.UTF-8 | en_US.UTF-8 | | libc |
template0 | postgres | UTF8 | en_US.UTF-8 | en_US.UTF-8 | | libc | =c/postgres +
| | | | | | | postgres=CTc/postgres
template1 | postgres | UTF8 | en_US.UTF-8 | en_US.UTF-8 | | libc | =c/postgres +
| | | | | | | postgres=CTc/postgres
(4 rows)
Tesdb-# \c
You are now connected to database "Tesdb" as user "postgres".
Tesdb-#
Tesdb-#
Tesdb-# \du
List of roles
Role name | Attributes | Member of
-----------+------------------------------------------------------------+-----------
postgres | Superuser, Create role, Create DB, Replication, Bypass RLS | {}
Tesdb=# \dt
List of relations
Schema | Name | Type | Owner
--------+-------------------+-------+----------
public | chat_conversation | table | postgres
public | employees | table | postgres
public | orgnaization | table | postgres
public | user | table | postgres
(4 rows)
Tesdb=# \dt+ employees
List of relations
Schema | Name | Type | Owner | Persistence | Access method | Size | Description
--------+-----------+-------+----------+-------------+---------------+------------+-------------
public | employees | table | postgres | permanent | heap | 8192 bytes |
(1 row)
Tesdb=# select schemaname,relname from pg_stat_user_Tables;
schemaname | relname
------------+-------------------
public | employees
public | user
public | chat_conversation
public | orgnaization
Tesdb=# select datname,oid from pg_database;
datname | oid
-----------+-------
postgres | 5
Tesdb | 16535
template1 | 1
template0 | 4
(4 rows)
how to connect database
-bash-4.2$ psql -U postgres Tesdb
psql (15.5)
Type "help" for help.
Tesdb=#
Tesdb=#
Tesdb=# \conninfo
You are connected to database "Tesdb" as user "postgres" via socket in "/var/run/postgresql" at port "5432".
creating os user:
+++++++++++++++++++
h-#
Tesdb-#
Tesdb-# \du
List of roles
Role name | Attributes | Member of
-----------+------------------------------------------------------------+-----------
postgres | Superuser, Create role, Create DB, Replication, Bypass RLS | {}
Tesdb-# \q
-bash-4.2$
-bash-4.2$
-bash-4.2$ createuser test
-bash-4.2$ psql
psql (15.5)
Type "help" for help.
postgres=# \du
List of roles
Role name | Attributes | Member of
-----------+------------------------------------------------------------+-----------
postgres | Superuser, Create role, Create DB, Replication, Bypass RLS | {}
test |
date and time
select now() -interval '2 hours 30 minutes' as deduct_time;
deduct_time
-------------------------------
2024-02-06 07:39:10.676531+03
(1 row)
select now() as current;
current
-------------------------------
