Master Advanced SQL for BI

Short summary

BI professionals can master query performance by using CTEs to modularize complex logic and window functions for time-intelligence calculations without self-joins. As analytics moves into AI-driven territory, clean SQL becomes critical context—poorly structured queries cause LLM hallucination. The post includes practical patterns: rolling averages, moving metrics, and YoY growth calculations.

• •CTEs break monolithic queries into modular, debuggable blocks with better optimizer performance
• •Window functions enable time-intelligence calculations (rolling averages, YoY) without complex self-joins
• •Clean SQL structure is essential input for AI-driven analytics—poorly structured queries cause LLM hallucination

Generated with AI, which can make mistakes.