Difference between revisions of "PostgreSQL"

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     postgres
 
     postgres
  
== Configuration files ==
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image: [[arm64v8/postgres]]
* <code>/etc/postgresql/10/main/[[postgresql.conf]]</code>
+
 
* <code>/etc/postgresql/10/main/[[pg_hba.conf]]</code> (PostgreSQL Client Authentication Configuration File)
+
 
 +
* Binaries: [[pg_isready]], [[psql]], [[pg_restore]]
 +
 
 +
== PostgreSQL ==
 +
* <code>[[bitnami/postgresql]]</code>
 +
* <code>[[bitnami/postgresql-ha]]</code>
 +
 
 +
== Configuration and data files ==
 +
* <code>/etc/postgresql/*/main/[[postgresql.conf]]</code>
 +
* <code>/etc/postgresql/*/main/[[pg_hba.conf]]</code> (PostgreSQL Client Authentication Configuration File)
  
 
  # "local" is for Unix domain socket connections only
 
  # "local" is for Unix domain socket connections only
 
  local  all            all                                    md5
 
  local  all            all                                    md5
 +
 +
* Data: <code>[[/var/lib/postgresql/]]</code>
  
 
== [[PostgreSQL logs]] ==
 
== [[PostgreSQL logs]] ==
*<code>[[/var/log/]]postgresql</code>
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*<code>[[/var/log/postgresql/]]</code>
  
 
== Basic Commands==
 
== Basic Commands==
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* Connect to a PostgreSQL database: <code>[[psql]] -h localhost -U postgres -d somedb</code><ref>http://postgresguide.com/utilities/psql.html</ref>
 
* Connect to a PostgreSQL database: <code>[[psql]] -h localhost -U postgres -d somedb</code><ref>http://postgresguide.com/utilities/psql.html</ref>
 
* Connect to a PostgreSQL database with a timeout of 5 seconds: <code>env PGCONNECT_TIMEOUT=5 psql -h localhost -U postgres -d somedb</code><ref>http://postgresguide.com/utilities/psql.html</ref>
 
* Connect to a PostgreSQL database with a timeout of 5 seconds: <code>env PGCONNECT_TIMEOUT=5 psql -h localhost -U postgres -d somedb</code><ref>http://postgresguide.com/utilities/psql.html</ref>
* [[Show databases]]: <code>SELECT datname FROM pg_database WHERE datistemplate = false;</code>
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* [[Show databases]]:
 +
** <code>[[\list]]</code>
 +
** <code>SELECT datname FROM pg_database WHERE datistemplate = false;</code>
 
* Show tables: <code>\dt</code> or <code>SELECT * FROM [[pg_catalog]].pg_tables;</code><ref>https://stackoverflow.com/questions/769683/show-tables-in-postgresql</ref>
 
* Show tables: <code>\dt</code> or <code>SELECT * FROM [[pg_catalog]].pg_tables;</code><ref>https://stackoverflow.com/questions/769683/show-tables-in-postgresql</ref>
* [[Show users]]: <code>\du</code>
+
* [[Show users]]: <code>[[\du]]</code>
 
* Drop DB: <code>[[dropdb]] DB_NAME</code>
 
* Drop DB: <code>[[dropdb]] DB_NAME</code>
  
 
* Describe ''employees'' table: <code>\d employees</code>
 
* Describe ''employees'' table: <code>\d employees</code>
* Show/List [[schema]]s: <code>select nspname from pg_catalog.pg_namespace;</code><ref>https://dba.stackexchange.com/questions/40045/how-do-i-list-all-schemas-in-postgresql</ref>
+
* Show/List [[schema]]s: <code>select [[nspname]] from [[pg_catalog]].pg_namespace;</code><ref>https://dba.stackexchange.com/questions/40045/how-do-i-list-all-schemas-in-postgresql</ref>
 
* Show version: <code>[[SELECT version();]]</code>
 
* Show version: <code>[[SELECT version();]]</code>
  
* Create backup: use <code>pg_dump</code> <ref>https://www.postgresql.org/docs/current/static/app-pgdump.html</ref> and <code>~/.pgpass</code> file for automating login.
+
* Create backup: use <code>pg_dump</code> <ref>https://www.postgresql.org/docs/current/static/app-pgdump.html</ref> and <code>[[~/.pgpass]]</code> file for automating login.
 
* Create user:  
 
* Create user:  
 
** <code>[[create user]] <username></code>
 
** <code>[[create user]] <username></code>
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* <code>[[systemctl status postgresql]]</code>
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* <code>systemctl [ [[systemctl status postgresql|status]] | [[systemctl stop postgresql|stop]] | [[systemctl start postgresql|start]] ] postgresql </code>
* <code>[[systemctl stop]] postgresql</code>
 
* <code>[[systemctl start]] postgresql</code>
 
  
* <code>[[\l]]</code>
+
 
 +
* <code>[[\l]], [[\du]], [[\dt]], [[\c]], [[\di]]</code>
  
 
== Processs ==
 
== Processs ==
 
* [[wal]] writer process
 
* [[wal]] writer process
 
  
 
== Related terms ==
 
== Related terms ==
* <code>[[/var/lib/postgresql/]]</code>
+
* [[Role]], [[Schema]]
 
* <code>[[pg_upgradecluster]]</code>
 
* <code>[[pg_upgradecluster]]</code>
 
* [[Adminer]]
 
* [[Adminer]]
* {{TOC operation databases}}
 
* [[ALTER DATABASE]]
 
 
* [[Amazon Redshift]]
 
* [[Amazon Redshift]]
* [[PostgreSQL statistics collector]]: <code>[[pg_stat]]*</code>
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* [[PostgreSQL monitoring]]
* [[MVCC]]
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** [[PostgreSQL statistics collector]]: <code>[[pg_stat]]*</code>
* [[Master]] user, [[Index (PostgreSQL)]]
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** <code>[[prometheus-postgres-exporter]]</code>
 +
* [[Multi-Version Concurrency Control (MVCC)]]
 +
* [[Index (PostgreSQL)]]
 
* [[Greenplum]]
 
* [[Greenplum]]
 +
* [[PostgreSQL replication]]
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* [[PGO PostgreSQL Operator]]
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* [[Amazon Aurora PostgreSQL Serverless]]
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* [[PgBouncer]] connection pooler
 +
* [[Amazon RDS for PostgreSQL]]
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* [[Master]] user for RDS: <code>[[postgres]]</code>
 +
* Ansible: <code>[[community.postgresql.postgresql_query]]</code>
 +
* [[psycopg2]]
 +
* [[PostgreSQL logging]]
 +
* <code>[[yum install postgresql]]</code>
 +
* <code>[[arm64v8/postgres]]</code>
 +
* [[Azure Cosmos DB for PostgreSQL]]
  
 
== Activities ==
 
== Activities ==
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== See also ==
 
== See also ==
* {{SQL}}
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* [[Patroni]] [[HA]] solution for PostgreSQL that requires <code>[[etcd]]</code>, <code>[[Zookeeper]]</code>, or <code>[[Consul]]</code>
 +
* {{PostgreSQL extensions}}
 
* {{PostgreSQL}}
 
* {{PostgreSQL}}
* [[Patroni]] [[HA]] solution for PostgreSQL that requires <code>[[etcd]]</code>, <code>[[Zookeeper]]</code>, or <code>[[Consul]]</code>
 
* {{DBs}}
 
  
 +
[[Category:PostgreSQL]]
 
[[Category:Databases]]
 
[[Category:Databases]]
  
 
{{CC license}}
 
{{CC license}}
 
Source: wikiversity
 
Source: wikiversity

Revision as of 17:54, 13 March 2024

wikipedia:PostgreSQL, often simply Postgres, is an object-relational database management system (ORDBMS). PostgreSQL is ACID-compliant and Transactional. PostgreSQL has updatable Views and Materialized view, Triggers, Foreign key; supports functions and stored procedures, and other expandability. PostgreSQL listens by default in TCP port 5432.

Installing PostgreSQL

MacOS

Linux, BSD variants

The easiest way to install PostgreSQL in these operating systems is to use their respective built-in package managers - for instance, the pkg command in DragonFlyBSD or apt in Debian and its derivatives. Be advised that there will be different variants of PostgreSQL available for install at a given point, specially regarding version numbers and client/server side. You should decide beforehand which version suits your needs for a particular application. Furthermore, you need to make sure that you have sufficient privileges in the system to install software (properly configured sudo/doas access, for example) or your install will fail.

Docker

docker run -p 5432:5432 --name MY_POSTGRES_DB -e POSTGRES_PASSWORD=mysecretpassword -d postgres[1]
* Docker-compose.xml PostgreSQL
docker run -p 5432:5432 -d \
   --name some-postgres \
   -e POSTGRES_PASSWORD=mysecretpassword \
   -e PGDATA=/var/lib/postgresql/data/pgdata \
   -v /custom/mount:/var/lib/postgresql/data \
   postgres
image: arm64v8/postgres


PostgreSQL

Configuration and data files

# "local" is for Unix domain socket connections only
local   all             all                                     md5

PostgreSQL logs

Basic Commands

Binaries: psql, pg_dump.

  • Connect to a PostgreSQL database: psql -h localhost -U postgres -d somedb[2]
  • Connect to a PostgreSQL database with a timeout of 5 seconds: env PGCONNECT_TIMEOUT=5 psql -h localhost -U postgres -d somedb[3]
  • Show databases:
    • \list
    • SELECT datname FROM pg_database WHERE datistemplate = false;
  • Show tables: \dt or SELECT * FROM pg_catalog.pg_tables;[4]
  • Show users: \du
  • Drop DB: dropdb DB_NAME
  • Create backup: use pg_dump [6] and ~/.pgpass file for automating login.
  • Create user:
    • create user <username>
    • ALTER USER user_name WITH PASSWORD 'new_password';
  • create database
  • Modify user privileges:
    • Privileges to create DB: ALTER USER user1 CREATEDB;



Processs

  • wal writer process

Related terms

Activities

See also

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Source: wikiversity

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