I stumbled upon a very interesting jOOQ question on Stack Overflow that required the calculation of a weighted average. Why is that. Problem description Assuming you have this database (using PostgreSQL syntax): create table transactions ( id bigint not null primary key, lines bigint not null, price numeric(18, 2) not null, profit numeric(18, 2) not … Continue reading Calculating Weighted Averages When Joining Tables in SQL
Tag: average
How to Emulate the MEDIAN() Aggregate Function Using Inverse Distribution Functions
Some databases are awesome enough to implement the MEDIAN() aggregate function. Remember that the MEDIAN() is sligthly different from (and often more useful than) the MEAN() or AVG() (average). While the average is calculated as the SUM(exp) / COUNT(exp), the MEDIAN() tells you that 50% of all values in the sample are higher than the … Continue reading How to Emulate the MEDIAN() Aggregate Function Using Inverse Distribution Functions