Inner Join DISTINCT

[xeonman13]

have three tables.
1.) Scheduled Courses
2.) Locations
3.) Course Types

Scheduled courses table has a list of courses, one column on that table is locationsid and another is coursetypes id.

I need to pull a list of course types, filtered by location.
So the coursetypesname is in the course types table and the location city is in the locations table.
This query needs to be DISTINCT but its not working. The query returns information but its duplicate data.

Any Ideas?
This is what it looks like

SELECT DISTINCT DISTINCT
scheduledcourses.scheduledcoursesid,
locations.locationcity,
coursetypes.coursetypesid,
coursetypes.coursetypename
FROM scheduledcourses  LEFT OUTER JOIN locations ON (scheduledcourses.courselocationid=locations.locationsid)  LEFT OUTER JOIN coursetypes ON (scheduledcourses.coursetype=courset

[johanafm]

xeonman13;10988680 wrote:

Scheduled courses table has a list of courses, one column on that table is locationsid and another is coursetypes id.

All of which are unique combinations, thus being distinct to begin with

xeonman13;10988680 wrote:

I need to pull a list of course types, filtered by location.

LEFT OUTER JOIN coursetypes ON (scheduledcourses.coursetype=courset

You have not provided a complete query, and since there is no where clause, there is no way to tell if this query really is filtering the result by a specific location.

xeonman13;10988680 wrote:

This query needs to be DISTINCT but its not working. The query returns information but its duplicate data.

No it doesn't. DISTINCT means the returned data will be distinct for each row. Thus

SELECT DISTINCT locationsid, coursetypeid
FROM scheduledcourse

SELECT DISTINCT coursetypeid
FROM scheduledcourse

these queries do not provide the same number of rows (unless each coursetypeid only appears once).

However, assuming that (locationid, coursetypeid) has to be unique, then adding

WHERE locationid = @someId

to both of the above queries then they would retrieve the same number of rows.