Re: Stupid Relationship question.
Re: Stupid Relationship question.
- Subject: Re: Stupid Relationship question.
- From: Ken Anderson <email@hidden>
- Date: Tue, 27 May 2008 12:12:17 -0400
Tom,
It all depends on how your keys are setup. Can you give us a little
more information on the relationship? For instance, do you have a
supervisorId attribute in Employee that will be null ? If so, a fetch
should not occur... it all depends on how the relationship is setup.
To EOF, if you have a value in a foreign key, then the related object
MUST exist. This becomes a problem when you have (what I call) side-
car tables, where the primary key of the sidecar is the same as the
primary key of the main table. In this case, your foreign key is
always non-null (since it's also your primary key), and therefore, EOF
assumes the object exists. One way to work around this is to create a
to-many relationship, call it 'supervisors', then have a custom method
in your EO, 'supervisor', that returns NULL or the first object in
'supervisors'.
Ken
On May 27, 2008, at 11:55 AM, Tom Jones wrote:
So, I'm just playing around with WO, and decided t make an
Organization Chart application. An employee has an optional to many
relationship employee>>direct_reports, and an optional to one
relationship employee>supervisor. The problem I have is when I try
to display an employee who has no supervisor, I get an exception
because when it tries to fetch the supervisor, it finds no matching
record. My expectation was that it would return null, rather than
raise an exception. What is the correct way to handle fetching
optional relationships?
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