In this talk, I’ll share how combinatorial testing and behavioral modeling helped uncover tricky edge cases while testing ClickHouse’s (open-source column-oriented DBMS) multiple authentication methods feature. I’ll demonstrate how these methodologies can systematically identify gaps in testing, validate complex features, and improve software quality. Attendees will learn practical steps for applying combinatorial testing to define comprehensive test scenarios, as well as how behavioral modeling can simplify result validation and solve the test oracle problem. This session is for QA engineers, testers, and developers looking to adopt smarter, more effective testing strategies.