OK, and so i do suck at MySQL, but here's essentially what I wish to do:

delete from course_plan_relationships
where course_plan_relationships.id not in ( 
    select course_plan_relationships.id
    from daily_plans inner join 
    course_plan_relationships on daily_plans.id=course_plan_relationships.daily_plan_id
);

To provide you with a concept of what is happening, I'll demonstrate the subquery and it is result:

mysql> select course_plan_relationships.id from daily_plans inner join 
course_plan_relationships on daily_plans.id=course_plan_relationships.daily_plan_id;
+----+
| id |
+----+
|  1 |
| 13 |
+----+

So essentially, I wish to remove all products in course_plan_associations, where its id area isn't for the reason that table I produced there within the subquery.

The mistake I recieve is:

ERROR 1093 (HY000): You cannot specify target table 'course_plan_relationships' for update in FROM clause

What I have essentially become is the fact that for whatever reason MySQL will not allow you to Remove or UPDATE with different sub-query including exactly the same table.

That's fine, and here is a supposed workaround: http://www.xaprb.com/blog/2006/06/23/how-to-select-from-an-update-target-in-mysql/

Nevertheless its for UPDATE and does not make use of the "in" syntax.

I am really a new comer to these items so any help could be super appreciated. I've not had any luck while using "AS blahothertablename" type of syntax (keep getting syntax errors), i can't learn how to keep initial subquery like a temporary result (again, syntax errors).

Using multi-table syntax within the remove, you do not need the sub-query:

DELETE course_plan_relationships
FROM course_plan_relationships LEFT JOIN
daily_plans ON course_plan_relationships.daily_plan_id = daily_plans.id
WHERE daily_plans.id IS NULL;

http://dev.mysql.com/doc/refman/5.0/en/delete.html

Based on your workaround, something similar to this will work:

delete from course_plan_relationships where course_plan_relationships.id not in 
(
  select x.id from 
   (
     select course_plan_relationships.id from daily_plans 
     inner join course_plan_relationships
     on daily_plans.id=course_plan_relationships.daily_plan_id
   ) AS x
) 

I believe this is the same as what you would like (presuming that course_plan_relationships.id may be the primary key on the table):

DELETE FROM course_plan_relationships AS cpr
WHERE NOT EXISTS
    ( SELECT *
      FROM daily_plans AS dp 
      WHERE dp.id = cpr.daily_plan_id
    ) ;