Find the most frequent value in each group, choose a tie policy, and compare categorical modes with averages and numeric percentiles.
The WINDOW Clause: Name a Window Once and Reuse It
Use the WINDOW clause to reuse partition and order rules, extend named windows with frames, and keep SQL Server calculations consistent.
Merging Overlapping Date Ranges Into Continuous Periods
Use running end dates when merging overlapping ranges, choose boundary rules, and return continuous periods without losing nested intervals.
Moving Averages in T-SQL
Moving averages in T-SQL use ROWS BETWEEN for rolling windows, but date gaps and duplicate dates decide what the result actually means.
SQL SERVER – Ranking Functions – RANK( ), DENSE_RANK( ), and ROW_NUMBER( ) – Day 12 of 35
RANK( ), DENSE_RANK( ), and ROW_NUMBER( ) return the same results until your data has a tie. Day 12 shows how each ranking function handles tied values.
Solving SQL Puzzles With Set-Based Thinking
Set-based thinking solves three SQL puzzles with grouping, anti-joins, and windows, then turns each solution into a repeatable query habit.
SQL SERVER – 2005 – Sample Example of RANKING Functions – ROW_NUMBER, RANK, DENSE_RANK, NTILE
SQL Server 2005 has four ranking functions: ROW_NUMBER, RANK, DENSE_RANK and NTILE. I explain what each returns and show a sample example of all four.