What do we mean by automated test data generation?

First let us clear up what is meant by Test automation? Test automation can be defined as the use of software system, program or application to carry out the following tasks:

- control the process of execution of tests
- to compare the actual outcomes with the predicted outcomes
- to set up the preconditions for test cases
- to keep test control and
- to implement the function of reporting tests.

WHY TEST AUTOMATION IS USED?
Test automation as the term itself suggests involves automation of a manual testing process which is already in progress.

- It is used for automating manual testing processes which use a formal approach for testing.

- Although manual testing also holds good for finding defects in a software program or application, it is a very laborious and time consuming testing process and also it is not so effective in finding certain kinds of defects.

- To overcome these drawbacks of manual testing, automated Testing is employed.

- It involves a process of writing a computer program or software to carry out testing that would otherwise requires to be done manually.

- Once the tests have been automated, they can be run, easily, quickly and repeatedly.

- All these plus points make the automated testing a very cost effective method for software applications.

- Even minor bugs or discrepancies can cause the program to break or crash over the lifetime of the application.

Two general approaches to test automation have been discovered so far:

- Code driven testing
Elements like classes, public interfaces, libraries and modules are tested under code driven testing with a assorted data arguments in order to validate the results for their correctness.

- Graphical user interface testing
As the name suggests this testing approach creates user interface events such as mouse clicks, key strokes etc. the changes that occur in the user interface are observed and that observable behavior is validated for its correctness.

TOOLS FOR TEST AUTOMATION
Unlike tools required for manual testing, test automation tools are quite expensive, and are usually employed or used in combination with the tools of manual testing.

- Nevertheless, the tools can be cost-effective in the longer term if used repeatedly in regression testing.

WAYS TO GENERATE DATA
Now coming to the automated test data generation, there are several ways for generating data and test cases.

- One of the ways to generate test cases automatically is model- based testing and it generates test cases through use of a model of the system.

- Data is the most important thing needed to execute any test.

- Generating data again and again for repeating tests becomes a time consuming task.

- You need to design the test data again and again to execute your test cases.

- You need to design the test data at the current instant if you are running tests in an exploratory manner.

- Generating test data on your own takes a lot of your valuable time.

- Automated tests need a large amount of distinct test data.

- Another alternative can be copying and pasting data for running tests if the production data is available.

- However, this does not prove to be a very good approach.

- But, nowadays several tools have been developed which can be used for automated test data generation.

So the good thing is that you need not waste your precious time generating test data by hand. These tools help you by creating large quantities of test data based on the conditions and constraints specified by you.

Automated test data generation has got the below mentioned benefits:
- Fast data generation
- Accurate data
- Uses built in algorithms
- Creates both valid and invalid test data
- Data is exportable