There are many types of database management systems available, starting from the file based system to the recent object-oriented database management systems. During the earlier days, we are talking about the first database management system; it was only a file based system. It was so simple with few capabilities and not that much efficient.

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In the hierarchical structure the data is organized as a tree structure and parent child segments. The parent child relationships are used to create links between the data in this model of database management systems. In this model there is one restriction that the child can have only one parent segment.

In the network model of the database management systems the drawback of the hierarchical model is overcome with the capability for the child to have more than one parent segment. The many-to-many relationship could be had in the network model of the database management system. Keep in mind that this does not mean that you cannot have a 1:1 relationship.

Then the Relational model of the database management system came into picture. This model was developed by Codd. This is more sophisticated than the previous models of the DBMS. Data structures can be defined, and definition of integrity constraints, storage and retrieval is also allowed. Some of the features of the RDBMS are the values are atomic, the columns have unique name and the values of the column are of the same kind. There is no significance to the order of the rows and the columns. Each of the rows in the RDBMS is unique.

The object-oriented database models can be programmed using the object-oriented programming languages like C++, Java, etc. while this retains the OO Language capability; the programmers can easily program the database in the native language. With this approach the objects of the language can be related to the objects of the database and helps you to manage the objects and improve performance.