“KQL” came to limelight around 2020. I started using KQL while working with Log Analytics Workspace in Azure, though it was just basic queries. However, I was not that keen to learn at that point. Over a period of time, KQL is gaining prominence.
Don’t get confused with Kibana Query Language as both are referred as KQL in short. Kusto Query Language is a powerful tool to explore your data and discover patterns, identify anomalies and outliers, create statistical modeling, and more.
Kusto is basically a data analytics cloud platform, optimized for interactive, adhoc queries over structured, semi-structured and unstructured data. Came as an internal tool and later became available for public as “Azure Data Explorer” in 2018. Azure Data Explorer was built on top of Kusto. Kusto Query Language is now used with multiple services with in Azure. The key one is Microsoft Sentinel.
Microsoft provides an lab environment for anyone who don’t have access to Azure to play around.
Give a try @ https://aka.ms/LADemo
Another option which can be used is Application Insight Demo platform.
Give a try @ https://aka.ms/AIAnalyticsDemo
Both demo environment require a Microsoft account however you can play around and learn the KQL without any worry.
Good luck !