The Nested Set Model is an approach to storing hierarchical data structures in relational databases ... finding depth of a node etc. For example, in Adjacency List it is impossible to find a path for ...

Although flat data structures serve to properly delineate between the individual entities in your service, there are cases where it may be more appropriate or convenient to use nested data structures.

Nested data parallelism: this feature offers the ... graphs or sparse matrices (see the examples above or in our library of algorithms). A language based performance model: this gives a formal way to ...