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# Decision Table Operator Sample

This sample shows how to use the TIBCO StreamBase® Decision Table operator.

## Introduction

The Decision Table operator evaluates a set of rules against each input tuple and emits an output tuple when a rule's conditions match the values in the input tuple.

The sample contains two StreamBase applications, each with a corresponding table in StreamBase native (`.sbdt`) format. The native format tables can also be replaced with their supplied respective tables in the Excel (`.xlsx`) format. The `decision-table.sbapp` application uses simple condition and action schemas and a small set of rules that illustrate the basic decision table rule syntax. The `decision-table-streambase-expressions.sbapp` application uses a more complex condition schema and set of rules that illustrate the use of StreamBase expressions in condition and action columns.

See Using the Decision Table Operator for a description of the operator's properties.

## Importing This Sample into StreamBase Studio

In StreamBase Studio, import this sample with the following steps:

- From the top-level menu, click File → Load StreamBase Sample.

- Enter `dec` to narrow the list of options.

- Select decision-table from the Data Constructs and Operators category.

- Click OK.

StreamBase Studio creates a single project for the operator samples.

## Running the Simple Decision Table Sample in StreamBase Studio

1. In the Project Explorer view, open the sample you just loaded.

   If you see red marks on a project folder, wait a moment for the project to load its features.

   If the red marks do not resolve themselves after a minute, select the project, right-click, and select Maven → Update Project from the context menu.

2. Open the `src/main/eventflow/`packageName`` folder.

3. Open the `decision-table.sbapp` file and click the Run button. This opens the SB Test/Debug perspective and starts the module.

4. In the Manual Input view, select the `Input` stream, enter `Jane Doe` in the `Name` field, and click Send Data.

5. In the Output Streams view, observe a tuple dequeued on the `Output` stream indicating a decision table rule has fired.

6. Experiment by entering other values in the `Name` and `Age` fields, clicking Send Data, and observing the resulting output tuples.

7. When done, press F9 or click the Terminate EventFlow Fragment button.

## Running the StreamBase Expressions Decision Table Sample in StreamBase Studio

1. In the Project Explorer view, open the sample you just loaded.

   If you see red marks on a project folder, wait a moment for the project to load its features.

   If the red marks do not resolve themselves after a minute, select the project, right-click, and select Maven → Project Update from the context menu.

2. Open the `src/main/eventflow/`packageName`` folder.

3. Open the `decision-table-streambase-expressions.sbapp` file and click the Run button. This opens the SB Test/Debug perspective and starts the module.

4. In the Manual Input view, select the `Input` stream, enter `Peter` in the `Name` field, and click Send Data.

5. In the Output Streams view, observe a tuple dequeued on the `Output` stream indicating a decision table rule has fired.

6. Experiment by entering other values in the fields, clicking Send Data, and observing the resulting output tuples.

7. When done, press F9 or click the Terminate EventFlow Fragment button.

## Sample Location

When you load the sample into StreamBase Studio, Studio copies the sample project's files to your Studio workspace, which is normally part of your home directory, with full access rights.

### Important

Load this sample in StreamBase Studio, and thereafter use the Studio workspace copy of the sample to run and test it, even when running from the command prompt.

Using the workspace copy of the sample avoids permission problems. The default workspace location for this sample is:

    studio-workspace/sample_decision-table

See Default Installation Directories for the default location of `studio-workspace` on your system.