Deepseek Coder is purpose-built for code tasks and handles SQL composition and debugging particularly well, making it the strongest fit for exploring unfamiliar schemas and fixing query logic. You can paste your schema or table definitions and ask it to generate, explain, or correct queries in plain conversation. Claude Sonnet is a strong alternative when you need more nuanced explanation of query behavior or want to reason through complex joins and subqueries. GitHub Copilot is worth considering if you prefer inline suggestions directly inside your editor as you write queries. ChatGPT o-series edges ahead for especially tricky debugging that benefits from step-by-step reasoning.