45. The system of claim 23 further including instructions that when executed by one or more computers cause the one or more computers to perform operations that include generating a results table including a results row for each test column, each results row indicating an output that will be generated given the input values of the test column.
45. The system of claim 23 further including instructions that when executed by one or more computers cause the one or more computers to perform operations that include generating a results table including a results row for each test column, each results row indicating an output that will be generated given the input values of the test column. 47. The system of claim 45 further including instructions that when executed by one or more computers cause the one or more computers to perform operations that include, in response to a user interaction with a results row, indicating which row of the rule specification will generate the output in that results row.