oam/knowledge base/postgresql.md

PostgreSQL

1. TL;DR
2. Further readings
   1. Sources

TL;DR

# Installation.
brew install 'postgresql@14'
sudo dnf install 'postgresql' 'postgresql-server'
sudo zypper install 'postgresql15' 'postgresql15-server'

# Connect to servers via CLI client.
# If not given:
# - the hostname defaults to 'localhost';
# - the port defaults to '5432';
# - the username defaults to the current user.
psql 'my-db'
psql 'my-db' 'user'
psql 'postgresql://host:5433/my-db?sslmode=require'
psql -U 'username' -d 'my-db' -h 'hostname' -p 'port' --password

# List available databases.
psql … --list

# Execute commands.
psql 'my-db' … -c 'select * from tableName;' -o 'out.file'
psql 'my-db' … -c 'select * from tableName;' -H
psql 'my-db' … -f 'commands.sql'

# Initialize a test DB.
pgbench -i 'test-db'
pgbench -i 'test-db' -h 'hostname' -p '5555' -U 'user'

# Create full backups of databases.
pg_dump -U 'postgres' -d 'sales' -F 'custom' -f 'sales.bak'
pg_dump … -T 'customers,orders' -t 'salespeople,performances'
pg_dump … -s

# Restore backups.
pg_restore -U 'postgres' -d 'sales' 'sales.bak'

Further readings

• Docker image
• Bidirectional replication in PostgreSQL using pglogical
• What is the pg_dump command for backing up a PostgreSQL database?

Sources

• psql
• pg_settings
• Connect to a PostgreSQL database