---
title: "Creating a Truth Table"
slug: "creating-a-truth-table"
description: "This document  demonstrates how to create a Truth Table in Decisions. This will allow a user the ability to compare possible combinations of inputs, that result in a different outcome depending on the specific combination."
tags: ["Rules", "truth table"]
updated: 2025-06-17T17:26:17Z
published: 2025-06-17T17:26:17Z
---

> ## Documentation Index
> Fetch the complete documentation index at: https://documentation.decisions.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Creating a Truth Table

## Overview

**Truth Tables** are a type of [Rule](/v9/docs/rules) that compares input data against multiple combinations sets of conditions that return a specific result.

In a Truth Table, conditions are divided into **Columns**, with specific combinations of these conditions forming **Rows**. Comparison values for conditions are defined as a **Cell**. ![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-17_13h17_14.png)

Note:The Truth Table evaluates the output based on **AND**condition across the column within the same row.

---

## Example

1. In a Designer Project, Select **CREATE RULE**
2. In the Gallery, select **Truth Table**from either the Favorites or Truth Table sections. Name the Truth Table, then hit CREATE. ![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-17_13h19_22.png)
3. The Truth Table Designer automatically opens.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-17_13h20_05.png)
4. Select SETUP INPUT DATA, then under Define Input Data, click DEFINE. ![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-17_13h20_28.png)
5. A window will open, and enter variables that the Truth Table will use. Click Save once finished.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-17_13h21_04.png)
6. Click Select Data Element for a column. A menu will appear listing configured input values. Select an input value, then CLOSE.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-17_13h22_54.png)
7. Another menu will appear, defining the condition verb for the column. These conditions will vary depending on the data type of the input. Select a condition, then click on Close.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-17_13h23_24.png)
8. The cells for the column will be updated to reflect the datatype of the input data. Select the pencil icon to define a comparison value for a cell in the column. Then CLOSE.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-17_13h24_00.png)
9. Repeat the process for the remaining row. Additional rows and columns can be added using [Truth Table Actions](/v9/docs/truth-table-actions).
10. Edit the output data for the Truth Table, if needed. ![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-17_13h24_53.png)
11. Select Debug in the Global Action Bar to begin debugging the Truth Table.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-17_13h25_12.png)
12. A window will open, allowing test values to be inputted.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-17_13h25_41.png)
13. Once values are inputted, click START DEBUGGING. The Truth Table will then evaluate the conditions for every cell in the Truth Table; if an entire Row evaluates as True, then the result data will be outputted.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-17_13h26_02.png)

---

## Optimizing Truth Tables

When using [Converter Flows](/v9/docs/using-converter-flows) with Truth Tables, it is recommended to enable [Outcome Caching](/v9/docs/outcome-caching) for these Flows to improve performance, as this can drastically improve the Table's execution time.

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For further information on Rules, visit the [Decisions Forum](https://community.decisions.com/categories/Rules).