SQLens

SQLens is a transparent TCP proxy that intercepts and analyzes SQL queries in real-time. It helps detect N+1 query patterns, slow queries, and provides a live performance dashboard—with zero code changes to your application.

Demo

Dashboard Overview

Features

• Transparent Proxy: Just point your app to SQLens instead of your DB.
• N+1 Detection: Automatically flags inefficient ORM patterns.
• Performance Guardrails: Real-time detection of SQL anti-patterns (e.g., SELECT *, missing WHERE).
• Data Privacy: Optional PII redaction mode to mask sensitive query values.
• Slow Query Tracking: Real-time latency measurement and visualization.
• Live Dashboard: Web-based interface to see what's happening under the hood.

Quick Start (with Docker)

1. Clone and Start:

   make docker-up

2. Access Dashboard: Open http://localhost:8080

3. Connect your App: Change your DB connection port from 5432 to 5433.

   Example psql connection:

   psql -h localhost -p 5433 -U user -d demo

Development & Testing

Prerequisites

• Go 1.23+
• Docker & Docker Compose (optional for local DB)

Commands

• make build: Compile the binary.
• make test: Run unit tests.
• make benchmark: Run a realistic load simulation script.

Configuration

SQLens can be configured via environment variables:

• SQLENS_LISTEN_ADDR: Proxy listen address (default :5433)
• SQLENS_TARGET_ADDR: Target database address (default localhost:5432)
• SQLENS_N1_THRESHOLD: Number of repeated queries to trigger alert (default 5)
• SQLENS_REDACT_SENSITIVE: Enable to mask sensitive data in logs/dashboard (default false)

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Built for SQL performance observability.