sql average by group code example

Example 1: sql group by sum

// Use SQL Group By clause after the Where clause
// Any column in the select list must either be in the Group By clause 
// or part of an agregation statement, like the Sum() statement
// Multiple columns can be included in the Group By Clause seperated by a comma
// Multiple columns stipulate the order tree. Order by 
// first column, then second ... etc

Select LastName, FirstName, Sum(LeaveDays), Max(age)
From EmployeeProjects
Where StartDate > '2020-01-01'
Group By LastName, FirstName

Example 2: sql avg and group by

SELECT
  AVG(depdelay),
  origin
FROM flight_delays
WHERE distance > 2000
GROUP BY origin;