Discover issues with Azure Functions and App Service using Application Insights

This article explains how to leverage Azure Application Insights and Kusto Query Language (KQL) to identify performance and execution issues in Azure Functions and Azure App Services. It covers use cases from professional experience, favorite KQL queries for telemetry analysis, troubleshooting guides, and template-based diagnostics. The author provides example queries to find long-running operations, sorted by request count or average duration, and demonstrates how to visualize results with charts. The content is focused on cloud monitoring, logging, and performance optimization for Azure-based applications.