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bakumbakum 

understanding relationship queries

Hi,

I have a custom object, Logistics_Event__c, which has a field which is a lookup to another custom object, Course__c. (I'm doing this with the PHP toolkit, by the way)

I want to query my Logistics Events and return fields from Course__c: Name and Version__c.

I've tried two ways with no luck:
SELECT
            l.Id,
            l.Start_Date__c,
            l.Number_of_Days__c,
            l.Location__c,
            Course__r.Name,
            Course__r.Version__c
            FROM Logistics_Event__c l

Gives me no error, but doesn't return any info.  There is not ALWAYS a course ID on the Logistics_Event__c record, but there is about 50% of the time.  I would have thought it would return nothing sometimes and the field data when there's data to return.

I also tried this way:
SELECT
            l.Id,
            l.Start_Date__c,
            l.Number_of_Days__c,
            l.Location__c,
            (SELECT Name, Version__c FROM Course__c)
            FROM Logistics_Event__c l

ERROR: Didn't understand relationship 'Course__c' in FROM part of query call

Can someone illuminate me?

Thanks!

-mb

ArtabusArtabus

Did you try child relationships ?

Something like this : select Name, Version, (Select Start_Date__c, Location__c from Logistics_Event__c) from Course__c

This should retrieve Courses, even if there is no Logistics Events associated.

bakumbakum
Thanks for the reply, but that's not what I want.  I want to retrieve the Logistcs Event, even if there is no course associated.  If there is a course associated, I want the course name and version.