Business Rules Tables are used to define acceptance tests for rules in your business domain that need to be tested with different sets of data.

The tables have a set of data columns and one or more assertion columns. If a set of input data (i.e., a rule) fails during execution, the remaining rows will still be executed.

A Business Rule Table has two kinds of columns:

• Input column - These columns represent input data for the given rule.
• Assertion column - These columns represent an expectation. The row fails if, during execution, the value of the column is different from the value specified. Assertion columns have a question mark at the end.

For example:

In Twist, a Business Rules Table to test the functionality for calculating Simple Interest might be described as follows.