KQL Window Functions: serialize, prev, next, row_number, row_cumsum, row_rank_dense, row_rank_min, row_window_session, scan Operator, and Every Pattern for Fabric Real-Time Analytics
The complete KQL window functions reference. The serialize operator and why window functions require it. prev() and next() for accessing adjacent rows. row_number() for sequential numbering. row_cumsum() for running totals. row_rank_dense() and row_rank_min() for ranking (dense vs gaps). row_window_session() for automatic session detection. The scan operator for stateful row processing. Partitioned windows with the restart parameter. KQL vs SQL window function comparison table. Eight real-world patterns, common mistakes, and interview Q&As.