4th Generation Techniques in Software Engineering

                         Software Engineering- Fourth Generation Techniques

             Implementation using a 4GL(4th Generation Techniques) enables the software developer to represent desired results in a manner that leads to automatic generation of code to create those results. Obviously, a data structure with relevant information must exist and be readily accessible by the 4GL. To transform a 4GT implementation into a product, the developer must conduct thorough testing, develop meaningful documentation, and perform all other solution integration activities that are required in other software engineering paradigms. In addition, the 4GT developed software must be built in a manner that enables maintenance to be performed expeditiously.


Software development environment that supports the 4GT paradigm includes some or all of the following tools: 
1) Non-procedural languages for database query 
2) Report generation 
3) Data manipulation
4) Screen interaction and definition
5) Code generation and High-level graphics capability 
6) Spreadsheet capability 
7) Automated generation of HTML and similar languages used for Web-site creation using advanced software tools.


Pros and Cons Proponents claim dramatic reduction in software development time and greatly improved productivity for people who build software. Opponents claim that current 4GT tools are not all that much easier to use than programming languages, that the resultant source code produced by such tools is "inefficient" and that the maintainability of large software systems developed using 4GT is open to question.

Advantages: 

 Simplified the programming process.

 Use non-procedural languages that encourage users and programmers to specify the results they want, while the computers determines the sequence of instruction that will accomplish those results. 

 Use natural languages that impose no rigid grammatical rules. 

Disadvantages: 

 Less flexible that other languages 

 Programs written in 4GLs are generally far less efficient during program execution that programs in high-level languages. 

Therefore, their use is limited to projects that do not call for such efficiency.