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Databases SQL Reporting by Example Day 2: Advanced Selecting Day 2: Review

olu adesina
olu adesina
23,007 Points
Posted by olu adesina
olu adesina
23,007 Points

sql help do i need to use the group by key word

Write a query to figure out how many employees are in each job role.

SELECT JOBS.ROLE, COUNT(1) FROM EMPLOYEES JOIN JOBS ON EMPLOYEES.JOB_ID = JOBS.ID ;

1 Answer

Billy Bellchambers
Billy Bellchambers
21,689 Points
Billy Bellchambers
Billy Bellchambers
21,689 Points

Group by is used as the name suggests to group values by a specific column value.

In this example it wants to do a count of the number of records against each value of Jobs.Role

To achieve this you can do the following.

SELECT JOBS.ROLE, COUNT(1)
FROM EMPLOYEES
JOIN JOBS ON EMPLOYEES.JOB_ID = JOBS.ID
GROUP BY JOBS.ROLE;

Should you want some further detail on the GROUP BY statement. https://www.w3schools.com/sql/sql_groupby.asp