When setting up a distributed database environment, if possibly a diverse database management system is used for some of the nodes that take part in this distributed database, then it is termed as a heterogeneous distributed database environment.

This environment can be represented as in the diagram here:

The following are some of the characteristics of the heterogeneous distributed database environment:

• Information is distributed between all the individual database management system's nodes
• A versatile database management system can be installed across the individual database systems
• Local users, who may want to interact with one of the individual database, can be given access to that individual database management system and the individual schema corresponding to it
• Users who want to access the global information can communicate with the distributed database management system, which has a global schema. It is a combination of all the individual database schemas

The heterogeneous distributed database environment is divided into two types, namely, systems and gateways.

The systems distributed database environment is the one that has full or partial functionality and belongs to a logical database, which is supported.

This environment is further categorized into Full DBMS Featured and Partly DBMS Featured distributed database environments.
A Full DBMS Featured distributed database environment is the one that has complete support for the entire functionality of a distributed database.
A Partly DBMS Featured distributed database environment is the one that has support for some of the distributed database features.

A Partly DBMS Featured distributed database environment is further categorized into Federated and Unfederated distributed database environments.

A Federated distributed database environment is the one that supports access provision to an individual database for specific information requests from the individual database.

A Federated DBMS Featured distributed database environment is further categorized into loosely integrated and tightly integrated distributed database environments.

A loosely integrated distributed database environment is the one with each of the individual databases that has its own individual schema. Each individual database management system should be able to interact with all the other individual schemas.

A tightly integrated distributed database environment is the one that has a global schema to define the entire information across all the individual databases.

An unfederated distributed database environment is the one that needs complete access to the central database component.

A gateways distributed database environment is the one that has connectivity to other databases through a simple path and does not support the logical database.