Parent/Child Vs One/Many

Hi

Just curious to know about the pros and cons of Parent/Child Vs One/Many.

We do use a bit of both. 
One big reason we use Parent child is we feel if we delete one global, it gets rid of all child data too and all parent child data is stored in one global. Much easier to manage.

 

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Answers

You are totally right.

With Parent-Child your data are not only logical but also physically tied to each other.

One-to-many allows you more flexible handling of Relations.

Just one out of many examples   M:N Relationship

Comments

Brendan's comment from the other thread summarizes it nicely. Here's a little more...you have 2 good alternatives to parent-children:

  • Without using either relationship option, just use a simple reference from the "many/child" class to the "one/parent" class, and add the FK constraint yourself (using "cascade"). This allows bitmap indexes in either class.
  • Simulate parent-children relationship using one-many. After setting up the one-many relationship, in the Relationship definition in the "many" class, add the bold items shown here: [Cardinality = one, Inverse = Orders, Required, OnDelete = cascade]. This allows bitmap indexes in either class.

Thanx Joel

Can you please elaborate point 1 a bit may be by a small example