I can understand the different between a multi-value field that contains
many objects and a Nested Document.
The main problem solvable by nested objects is "cross object" matching, see
But why would I use a nested object vs. a parent object & one or more
For query that includes the child, I can use a has_child query (or filter)
For a query that includes a nested document I can use a nested_ query
Both result in 1 document for the parent and 1 for each child.
Is one of the primary differences between nested object and a
child/parent is that
A nested type is defined/changed/deleted by indexing a new parent
while a child document can have a different lifecycle than its parent?
My application of parent/child would definitely be a case where the
children come along at different times after the parent is created.