Building Your T-SQL Tool Kit: Window Function Fundamentals
Have you pulled a script to identify duplicates from a blog post, but couldn’t quite get it to work, because you weren’t sure what that ROW_NUMBER() function was doing. Maybe you heard talk about creating running totals without using sub-queries, but you got frustrated when the groups weren’t totaling correctly. Or maybe, you’ve never even heard of Window Functions. All are good reasons to attend this demo-filled session which demystifies this versatile T-SQL tool. First, we’ll break apart the OVER clause, the key to understanding how window functions work. Then we’ll expand on each group of functions that can use the OVER clause: ranking, aggregate, and analytic functions. Finally, we’ll look at real scenarios where this tool works and talk about performance considerations. When you leave, you’ll have the fundamentals you need to fully develop your mastery of Window Functions.
Christina Leo is a Netherlands based, independent consultant specializing in T-SQL development and performance tuning. She happily shares her 14 years of technical experience with the SQL Server community by teaching at local and international SQL Server user group meetings and technical events, including multiple SQL Saturdays, SQL Bits, TechEd Africa, and the PASS Summit.