Defining Lookup Tables as Decision Tables

• A lookup table is really just a simple decision table, usually with one input attribute mapping to one output value.
• The only way in which this differs from a regular decision table is that
• • when you use the designation "lookup" you are guaranteeing that there will only ever be one output value for any given input value.
• • you can only have one input variable per table; otherwise its just a normal decision table.
• This restriction enables the underlying execution engine to process the table in a more efficient manner.

Requirements

1. Single attribute tested. Though you can have many condition line that apply to that attribute.
2. Single output set
3. All possible values accommodated
4. Should be able to display vertically
5. Also consider 2 dimensional lookups

see also Defining Multi‐Dimensional Spreadsheets as Decision Tables