crypto_trader/docs/deployment/postgresql.md

PostgreSQL Setup

This guide covers optional PostgreSQL database configuration.

When to Use PostgreSQL

PostgreSQL is recommended for:

• Large datasets (millions of trades)
• Multiple users
• Advanced queries
• Production deployments
• High-performance requirements

Installation

Install PostgreSQL

Fedora/Bluefin:

sudo dnf install postgresql postgresql-server
sudo postgresql-setup --initdb
sudo systemctl enable postgresql
sudo systemctl start postgresql

Ubuntu/Debian:

sudo apt-get install postgresql postgresql-contrib
sudo systemctl enable postgresql
sudo systemctl start postgresql

Database Setup

Create Database

sudo -u postgres psql

CREATE DATABASE crypto_trader;
CREATE USER crypto_trader_user WITH PASSWORD 'your_password';
GRANT ALL PRIVILEGES ON DATABASE crypto_trader TO crypto_trader_user;
\q

Configure Connection

Update config.yaml:

database:
  type: postgresql
  host: localhost
  port: 5432
  database: crypto_trader
  user: crypto_trader_user
  password: ${DB_PASSWORD}  # Use environment variable

Set Environment Variable

export DB_PASSWORD='your_password'

Or add to ~/.bashrc:

echo 'export DB_PASSWORD="your_password"' >> ~/.bashrc

Migration from SQLite

Export from SQLite

sqlite3 trading.db .dump > dump.sql

Import to PostgreSQL

psql -U crypto_trader_user -d crypto_trader -f dump.sql

Performance Tuning

PostgreSQL Configuration

Edit /etc/postgresql/*/main/postgresql.conf:

shared_buffers = 256MB
effective_cache_size = 1GB
maintenance_work_mem = 64MB
checkpoint_completion_target = 0.9
wal_buffers = 16MB
default_statistics_target = 100
random_page_cost = 1.1
effective_io_concurrency = 200
work_mem = 4MB
min_wal_size = 1GB
max_wal_size = 4GB

Indexes

Key indexes are created automatically. For custom queries, add indexes:

CREATE INDEX idx_trades_symbol_date ON trades(symbol, executed_at);
CREATE INDEX idx_market_data_symbol_timeframe ON market_data(symbol, timeframe, timestamp);

Backup and Recovery

Backup

pg_dump -U crypto_trader_user crypto_trader > backup.sql

Restore

psql -U crypto_trader_user crypto_trader < backup.sql

Automated Backups

Set up cron job:

0 2 * * * pg_dump -U crypto_trader_user crypto_trader > /backup/crypto_trader_$(date +\%Y\%m\%d).sql

Security

Connection Security

• Use strong passwords
• Restrict network access
• Use SSL connections for remote access
• Regular security updates

User Permissions

• Use dedicated database user
• Grant only necessary permissions
• Don't use superuser for application

Troubleshooting

Connection refused?

• Check PostgreSQL is running: sudo systemctl status postgresql
• Verify connection settings
• Check firewall rules

Authentication failed?

• Verify username and password
• Check pg_hba.conf configuration
• Review PostgreSQL logs

Performance issues?

• Check PostgreSQL configuration
• Review query performance
• Add appropriate indexes
• Monitor resource usage