I am spending a lot of time trying to figure out how this ORM stuff works on the Air side of things.  The lack of documentation makes it very difficult to determine if a problem I am encountering is a bug, or an error in how I have something implemented.

In this case, I think it is a bug (which I have logged in the ColdFusion 9 Bug Database [EDIT: Bug Verified by Adobe 1/13/2010] [EDIT: Bug Fixed 1/25/2010 ColdFusion 9.0.1 ,Beta 1, Build 268370]).  It has to do with recursive self joins (I'm sure there is a much cooler sounding name for it, but that's all I've got).  Here's an example of what I mean.

Like most of my tables, the Users table in my database has a created_by_users_ID column that holds the user ID of the person who created that specific user record.  It also has a modified_by_users_ID, which just as it's name suggests contains the user ID of the user who last modified the user record.

Here's my CFC entity (well, scaled down to be more meaningful)

<cfcomponent persistent="true" table="users" output="false" alias="Users">
    <!---- properties ---->
    <cfproperty name="ID" column="ID" type="numeric" ormtype="int" fieldtype="id"  />        
    <cfproperty name="user_name" column="user_name" type="string" ormtype="string" />        
    <cfproperty name="password" column="password" type="string" ormtype="string" />        
    <!---- relationships ---->
    <cfproperty name="createdByUser"  fieldtype="many-to-one" cfc="users" fkcolumn="created_by_users_ID" />
    <cfproperty name="modifiedByUser"  fieldtype="many-to-one" cfc="users" fkcolumn="modified_by_users_ID" />
</cfcomponent>

And here's the Users.as entity:

package com.myproject.model.vo
{   
    [Bindable]
    [RemoteClass(alias="Users")]
    [Entity]
   
    public class Users
    {  
        [Id]
        public var ID:int;
        public var user_name:String;
        public var password:String;
   
    // Relationships
    [ManyToOne(targetEntity="com.myproject.model.vo::Users",fetchType="EAGER")]
    [JoinColumn(name="created_by_users_ID",referencedColumnName="ID")]                
    public var createdByUser:Users;

    [ManyToOne(targetEntity="com.myproject.model.vo::Users",fetchType="EAGER")]
    [JoinColumn(name="modified_by_users_ID",referencedColumnName="ID")]                
    public var modifiedByUser:Users;
       
        public function Users()
    {
    }  
    }
}

Super simple.

Now if I call my fetchCFC tester method (which basically does <cfdump var="#EntityLoad(arguments.entity)#">) I get my Users output as expected.  I also see this in my joined columns:

Notice the [see cfc. for users details].  This is how CF is handling the recursions.  Good.  Now when I try to fetch from the Flex/Air side I get a infinite loop that slowly eats away all my memory until I end the adl.exe process.  Note: Stopping the debugging session doesn't kill the adl.exe in this case, I have to kill it via task manager.

Maybe there's a way to prevent this, but I can't find any documentation.  For now I've simply removed the relationships from the Users entity (as it is currently the only one that joins to itself) and I just manually update the integer values with the PK value of the appropriate user record.

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