Sub-setting

Sub-setting DEFINITION

**Subsetting is a method of selecting a predefined data sub-set necessary for testing some particular development iteration of the code at specified environment.

DEVELOPMENT LIFECYCLE

Let's consider the data origination and movement in the development lifecycle.

FIRST ITERATIONS. Coding from scratch.

Any development starts with the idea, which translates into code, and this code is tested with some data. Test use cases define which data to use and create. At this stage, it is important to find data sources, and the random components that contain data sets are easy to use for this purpose, as well is the 'regular expression' component. The amount of data necessary to test in that stage of the development is usually the bare minimum needed to test use cases, mainly for functional requirements. Of course, non-functional requirements are taken into account in the architecture, but the time to test them is usually on a bigger and more system-like environment than the developer's sandbox.

This development stage is the first iteration of code.

TEST ENVIRONMENTS

When the first iteration of code is complete, often times developers push the code to the integration environment and to the testers where the amount of test cases increases to test regression and some non-functional requirements such as ease of product use, security, etc. Continuous integration environments are used in the teams with best practices based on method of Grady Booch and adopted by extreme programming agile methodology.