What is the difference between Hierarchical Database and Relational Database?

The hierarchical database seems more simple than the relational database, as it employs the logical parent-child relationship. A relational database, on the other hand, includes the use of tables to keep records in the form of table fields. In addition, a unique key is required for each record. A hierarchical database happens to be the processor for all other databases, and it has been in existence before the discovery of the relational database.

A category of data is referred to as "segments" in the hierarchical database, while a category of data is referred to as "fields" in a relational database. In a hierarchical database, every child segment inherits its parent's properties; while in the relational database, there are no data levels and no scenario of inheritance. A child is linked to its parent in the hierarchical database, and the segments are linked explicitly; while foreign keys and primary keys are used to link tables in the relational database in an explicit manner.

The hierarchical database is composed of different segments that are connected to each other. These segments are joined together. One segment will usually have the parent segments and child segments so that it will be easier to understand the hierarchy of the items that are involved.

With a relational database, there are usually complete tables that need to be joined together to show that these two tables are related to each other. To show that two tables are related to each other, there is a need to place some foreign and primary keys in the process. You can easily tell if you are looking at a hierarchical or relational database depending on how they look. The hierarchical database will be tree-like.