postgres

name	postgres
description	Execute read-only SQL queries against multiple PostgreSQL databases. Use when: (1) querying PostgreSQL databases, (2) exploring database schemas/tables, (3) running SELECT queries for data analysis, (4) checking database contents. Supports multiple database connections with descriptions for intelligent auto-selection. Blocks all write operations (INSERT, UPDATE, DELETE, DROP, etc.) for safety.
license	Apache-2.0
metadata	{"author":"sanjay3290","version":"1.0"}

PostgreSQL Read-Only Query Skill

Execute safe, read-only queries against configured PostgreSQL databases.

Requirements

• Python 3.10+
• psycopg2-binary: pip install -r requirements.txt

Tip: For new projects, consider psycopg (v3) (pip install psycopg[binary]) as the recommended modern PostgreSQL adapter. It offers async support, pipeline mode, and better typing. psycopg2 remains supported but is in maintenance mode.

Setup

Create connections.json in the skill directory or ~/.config/claude/postgres-connections.json.

Security: Set file permissions to 600 since it contains credentials:

chmod 600 connections.json

{
  "databases": [
    {
      "name": "production",
      "description": "Main app database - users, orders, transactions",
      "host": "db.example.com",
      "port": 5432,
      "database": "app_prod",
      "user": "readonly_user",
      "password": "your-password",
      "sslmode": "require"
    }
  ]
}

Config Fields

Field	Required	Description
name	Yes	Identifier for the database (case-insensitive)
description	Yes	What data this database contains (used for auto-selection)
host	Yes	Database hostname
port	No	Port number (default: 5432)
database	Yes	Database name
user	Yes	Username
password	Yes	Password
sslmode	No	SSL mode: disable, allow, prefer (default), require, verify-ca, verify-full

Usage

List configured databases

python3 scripts/query.py --list

Query a database

python3 scripts/query.py --db production --query "SELECT * FROM users LIMIT 10"

List tables

python3 scripts/query.py --db production --tables

Show schema

python3 scripts/query.py --db production --schema

Limit results

python3 scripts/query.py --db production --query "SELECT * FROM orders" --limit 100

Database Selection

Match user intent to database description:

User asks about	Look for description containing
users, accounts	users, accounts, customers
orders, sales	orders, transactions, sales
analytics, metrics	analytics, metrics, reports
logs, events	logs, events, audit

If unclear, run --list and ask user which database.

Safety

• Read-only mode (readonly=True) + query validation (SELECT/SHOW/EXPLAIN/WITH only)
• Single statement per query, 30s timeout, 10K row limit
• SSL configurable, credentials sanitized in error output

Troubleshooting

Error	Solution
Config not found	Create connections.json in skill directory
Authentication failed	Check username/password in config
Connection timeout	Verify host/port, check firewall/VPN
SSL error	Try "sslmode": "disable" for local databases
Permission warning	Run chmod 600 connections.json

Workflow

1. Run --list to show available databases
2. Match user intent to database description
3. Run --tables or --schema to explore structure
4. Execute query with appropriate LIMIT