Sales Use Case: Ranking/Window Functions
Angelo Bobak · Apress eBooks · 2023
This is our last chapter dealing with the sales data warehouse. We will look at the third category of functions called window or ranking functions. We will take the same approach as prior chapters, that is, provide a brief explanation of the function, present the code and the query results, and do some performance analysis and tuning by adding indexes and report tables. Lastly, we will present a data analysis problem called gaps and islands where we use some of the window system functions we studied in Chapter 3 to identify gaps and sequences in dates for sales data.