Abstract:

Recently, the most used databases are relational and NoSQL databases. However, in relational databases, there is no inheritance, which is important when we want to use this Database with the object-oriented application. Furthermore,NoSQOL databases are less consistent and unsecure than relational databases. In this article,  we present the flexible Database (FDB) concept.this concept makes it possible to improve the relational database model with inheritance and make more flexible changes to the structure of the database while using it.