Enrollments closing soon for Post Graduate Certificate Program in Applied Data Science & AI By IIT Roorkee | 3 Seats Left
Apply NowOuter joins are for finding records that may not have a match in the other table. You specify which side of the join is allowed to have a missing record.
left outer join (or just left join) -> Table on right side can have missing records
right outer join (or just right join) -> Table on left side can have missing records
select
e.empid
, concat(e.empfname,' ',e.emplname) "employee"
, e.mgrempid
, concat(m.empfname,' ',m.emplname) "manager"
from emp e left outer join emp m
on e.mgrempid = m.empid
order by 1,2
;
In above example, empid 1 doesn't have manager id, so manager name will be displayed as NULL rather than not displaying row for empid 1 at all.
Taking you to the next exercise in seconds...
Want to create exercises like this yourself? Click here.
No hints are availble for this assesment
Answer is not availble for this assesment
Loading comments...