Query your PostgreSQL data with AI — step by step. We'll show you both the manual approach and the faster way with Contextary.
It's entirely doable. Here's what you'll need to set up and maintain.
Gather your host, port (usually 5432), database name, username, and password. If you're connecting to a managed service like RDS, Supabase, or Neon, you'll also need to figure out the right connection format and any IP allowlisting requirements.
Find a community MCP server that supports PostgreSQL, or write your own script to expose query capabilities to Claude. The Postgres ecosystem has a few options, but you'll need to evaluate whether they support read-only mode, parameterized queries, and proper error handling.
Production Postgres databases usually require SSL connections. You'll need to configure the right sslmode (require, verify-ca, verify-full), handle certificate files, set appropriate connection timeouts, and potentially configure connection pooling to avoid exhausting your connection limit.
Document every table, column, and relationship in a system prompt for Claude. For a typical SaaS application database, this means describing the users, accounts, subscriptions, events tables and all their relationships, foreign keys, and indexes.
Which columns are nullable and what null means in context. Which tables use soft deletes (deleted_at IS NOT NULL). What "active" means for users versus subscriptions. Which status values are valid versus deprecated. Miss one, and Claude will silently produce wrong results.
Claude's first query will almost certainly include soft-deleted records and test accounts. You'll re-prompt with "exclude records where deleted_at is not null" and "filter out accounts where email ends in @test.com." Then you'll do it again next conversation, because Claude doesn't remember.
Application databases change frequently — new tables for new features, renamed columns during refactors, migrated fields. Every change means updating your system prompt, and there's no automated way to know when it's out of date.
Share your system prompt with your team via Slack or a Google Doc. Watch as everyone copies it, modifies it slightly, and ends up with their own version. The analyst uses one definition of "active customer," the PM uses another, and the weekly report uses a third.
But you'll spend more time managing prompts and copying SQL than actually getting answers. And every person on your team has to set this up independently.
Same result, fraction of the effort. Here's the entire setup.
Enter your Postgres connection details — host, port, database, user, and password. Contextary handles SSL configuration, connects to your database, and discovers your schema automatically. Works with RDS, Supabase, Neon, and any standard Postgres deployment.
Every table, column, data type, constraint, and foreign key relationship is mapped automatically. No manual DDL copy-pasting, no deciding what to include, no context window limits.
Document soft delete conventions, test account filters, metric formulas, and business rules. AI suggests most annotations based on your schema — flag soft deletes once, and every query automatically excludes deleted records.
One config line connects Claude to Contextary via MCP. Claude gets access to your full schema, all your team's knowledge, and the ability to run read-only queries directly against your database.
Ask Claude anything about your PostgreSQL data. It knows about your soft deletes, your test accounts, your metric definitions. Contextary provides the context, Claude writes the SQL, Contextary tells your database what query to run, and you get the answer — accurate, consistent, every time.
When someone adds a gotcha or updates a metric definition, every AI tool sees it immediately. No prompt maintenance, no context window limits, no re-explaining.
| Without Contextary | With Contextary | |
|---|---|---|
| Setup time | Hours of prompt engineering | 60 seconds |
| Schema changes | Manual prompt updates | Auto-discovered |
| Business rules | Copy-pasted into prompts | Documented once, shared everywhere |
| Team consistency | Everyone writes their own prompt | One source of truth |
| Metric definitions | Explained each time | Defined with exact formulas |
| Query execution | Copy-paste between tools | Contextary runs it for you |
| Maintenance | Ongoing prompt management | Set it and forget it |
Connect PostgreSQL to Claude in 60 seconds. Free to get started.