Rank() and Percent_Rank()

Author: ptyadana

Advanced SQL for Data Science - Time Series/02.Commonly used Functions for Time Series/03.Rank and Percent Rank.sql

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+---------------------  RANK ()  ---------------------------
+
+-- we use Rank() when we want to know the relative oder of particular rows relative to other rows. (such as 1, 2, 3, etc.)
+-- the ranking 1, 2, 3 will restart when it reaches to another unique group.
+-- works same as Row_Number Function
+
+
+SELECT dept_id, server_id, cpu_utilization,
+	RANK() OVER (PARTITION BY dept_id ORDER BY cpu_utilization DESC)
+FROM time_series.vw_utilization
+WHERE event_time BETWEEN '2019-03-05' AND '2019-03-06';
+
+
+---------------------  PERCENT_RANK ()  ---------------------------
+-- it is the rank divided by total numbers of rows (example: 0.0002, etc)
+
+SELECT dept_id, server_id, cpu_utilization,
+	PERCENT_RANK() OVER (PARTITION BY dept_id ORDER BY cpu_utilization DESC)
+FROM time_series.vw_utilization
+WHERE event_time BETWEEN '2019-03-05' AND '2019-03-06';
+
+
+