Hierarchial databases
Hierarchial databases
Records held in a flat file are held in a sequential order. In other words, the records come one after another. In a relational database, the records are also ordered sequentially within each table. A hierarchical database organises records differently, using a tree structure. Each record has attached to it a number of pointers. These pointers link one record to the record above and below it in the tree. As you go to a lower level in the tree, you can retrieve ever more detailed information.
Here is part of a diagram of a hierarchical database as an example:
