DDE (Data Drive Engine) is a python-based tool that helps extend typical Excel functionalities, like its formulae and macros. On top of that, the tool allows to create massive amounts of data that follows a specified template, characterized by a set of rules. This will greatly enhance the effectiveness of testing, specifically automated and performance testing.
At the heart of the program is the concept of a data template, that, simply put, is a textual representation of an excel sheet. The tool comes with a built-in pre-processor, that could optionally generate a template from an existing excel sheet. It could now be manually extended with custom rules, and in turn used to create huge amounts of customized data, to easily fill up the web page during a performance test run. Of course, a template could also be hand-written from the scratch, allowing much more flexibility.
The rules could vary in complexity and can handle simple data validation (as seen in Excel) rules, to very complicated user-defined functions (as defined from Python). It also supports the cross-references between excel cells, INDIRECT references (as supported in Excel), and has built-in concatenation methods, both of which are available out-of-the-box.
For more insights into workflow, usage instructions, and prerequisites of the tool, see Help documentation