4. Database Users

The database users fall into several categories:

1. Application Programmers

Application programmers are computer professionals interacting with the system through DML calls embedded in a program written in a host language (e.g. C, PL/1, Pascal). These programs are called application programs. 

The DML precompiler converts DML calls (prefaced by a special character like $, #, etc.) to normal procedure calls in a host language. The host language compiler then generates the object code. Some special types of programming languages combine Pascal-like control structures with control structures for the manipulation of a database. These are sometimes called fourth-generation languages. They often include features to help generate forms and display data.

 2. Sophisticated Users

 Sophisticated users interact with the system without writing programs. They form requests by writing queries in a database query language. These are submitted to a query processor that breaks a DML statement down into instructions for the database manager module.

3. Specialised Users

 Specialised users are sophisticated users writing special database application programs. These may be CADD systems, knowledge-based and expert systems, complex data systems (audio/video), etc.

4. Naive Users

Naive users are unsophisticated users who interact with the system by using permanent application programs (e.g. automated teller machine).