The Problem
LLMs often hallucinate destructive SQL commands (DROP TABLE, DELETE). Connecting them directly to production databases is a massive security risk, as they lack inherent context or safety boundaries.
The Solution
I built a custom MCP Server in Golang that acts as a secure middleware “Gatekeeper”.
- Technology: Golang, Model Context Protocol, PostgreSQL, AST Parsing (
xwb1989/sqlparser). - Key Feature: It utilizes a deterministic AST-based SQL parser to strictly block any non-SELECT statements before they ever touch the database connection pool.
Key Metrics
- 0% Data Loss incidents in testing i.e. 100% Block rate for destructive commands (DROP/DELETE).
- <10ms parsing latency overhead.
- Protocol: Implemented full Model Context Protocol (MCP) compliance.