database-query

Database Query

Execute SQL against PostgreSQL or MySQL via CLI.

Environment Variables

• DATABASE_URL - PostgreSQL connection string (e.g. postgres://user:pass@host:5432/db)
• MYSQL_HOST, MYSQL_USER, MYSQL_PASSWORD, MYSQL_DATABASE - MySQL connection params

PostgreSQL

psql "$DATABASE_URL" -c "SELECT id, name FROM users LIMIT 10;"

CSV output:

psql "$DATABASE_URL" --csv -c "SELECT * FROM orders WHERE created_at > now() - interval '7 days';"

List tables:

psql "$DATABASE_URL" -c "\dt"

Describe table:

psql "$DATABASE_URL" -c "\d users"

MySQL

mysql -h "$MYSQL_HOST" -u "$MYSQL_USER" -p"$MYSQL_PASSWORD" "$MYSQL_DATABASE" -e "SELECT id, name FROM users LIMIT 10;"

Safety

• Always use LIMIT on SELECT queries unless the user explicitly asks for all rows.
• Never run DROP, TRUNCATE, or DELETE without explicit user confirmation.
• Prefer read-only queries. If a write is needed, confirm with the user first.