On Thu, Apr 7, 2016 at 3:41 PM, Ann Harrison <[email protected]> wrote:
> On Thu, Apr 7, 2016 at 2:27 PM, Gabor Boros [email protected] > [firebird-support] <[email protected]> wrote: > >> 2016. 04. 07. 19:31 keltezéssel, 'Mark Rotteveel' [email protected] >> [firebird-support] írta: >> > > Just in case you think Firebird should be able to ignore parts of an outer join, let me disillusion you. > select d.DepartmentName from Departments d > *left outer* join Employees e on e.DeptID = d.DeptID > > Suppose you have 10 Departments and 10 Employees, but all the > Employees have the same DeptID. Then you should get the same > DepartmentName ten times. > The left outer join will return the nine unmatched Departments, returning one DepartmentName for each unmatched Department. The name of the Department with 10 Employees will be returned 10 time. Good luck, Ann > > > > >
