PGNexus-AI: An Intelligent and Secure Natural-Language PostgreSQL Administration Framework

Modern teams depend on PostgreSQL for mission-critical workloads, yet administration is still done by hand-writing SQL in disconnected tools such as psql, pgAdmin and DBeaver, while AI assistants such as GitHub Copilot have no live connection to the database and cannot read its schema, execution plans or error output. LLM-generated SQL also introduces new injection-style security risks. This paper presents PGNexus-AI, a PostgreSQL-only desktop IDE that combines Google Gemini, Gemma 4 and GitHub Copilot behind a schema-grounded orchestration layer. It provides natural-language-to-SQL generation, execution-plan-driven query optimization, automatic error diagnosis and correction, and AI-generated schema documentation with column-relationship mapping. A defense-in-depth safety layer (parameterization, query preview and confirmation, read-only and sandbox execution, role-based scoping and injection screening) protects production databases, and GitHub integration version-controls SQL and migrations. We describe the architecture, methodology and an evaluation plan covering efficiency, reliability, optimization and security.