I've got a table which contains object_id, object_name, derived_from_object_id

What function(s) do I need to look at to be able to provide a total count of derivations based on a provided object_id?

Example
1 object1 0
2 object2 1
3 object3 1
4 object4 0
5 object5 3
6 object6 2
7 object7 3
8 object8 5

There is no defined maximum number of derivations from an object or the children. So if I wanted a total count from objectid 1 the result would be 7.

I've thought about writing a stored procedure which simply returned a count for each object id, it would then call itself for each id that there was a child for. Whilst I think this would work I think it's completely the wrong direction to go.

I've got a table which contains object_id, object_name, derived_from_object_id

What function(s) do I need to look at to be able to provide a total count of derivations based on a provided object_id?

Example

1    object1    0  
2    object2    1  
3    object3    1  
4    object4    0  
5    object5    3  
6    object6    2  
7    object7    3  
8    object8    5  

There is no defined maximum number of derivations from an object or the children. So if I wanted a total count from objectid 1 the result would be 7.

I've thought about writing a stored procedure which simply returned a count for each object id, it would then call itself for each id that there was a child for. Whilst I think this would work I think it's completely the wrong direction to go.