There are two main types of objects inside a database: containers and objects themselves. There is a nested structure where there are ten root container objects: the nine symbol tables and the named object dictionary which contains objects or other containers.
Objects can belong to the database or not. An object is considered to be owned by the database (database resident object) if it has been added to the appropriate container. For example, a Layer object belongs to the database if it's added to the layer table container, a Block object belongs to the database if it's added to the block table, and an entity belongs to the database if it's added to a block table record that is in the block table, and so on. Objects that are not put in the database are non-resident objects.
For example, the procedure of creating a new layer object inside the database looks like:
Another example is creating an entity inside model space of the drawing. Here is the procedure:
Since a created object becomes a database resident object, its lifecycle is managed by the database.
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