# tSample MapReduce properties (deprecated)

Availability-note[Deprecated](https://help.talend.com/r/en-US/Cloud/labels-on-talend-help-center/availability-deprecated)

This content is deprecated.

These properties are used to configure tSample running in the MapReduce Job framework.

The MapReduce tSample component belongs to the Processing family.

The component in this framework is available in all Talend products with Big Data and Talend Data Fabric.

Availability-note[Deprecated](https://help.talend.com/r/en-US/Cloud/labels-on-talend-help-center/availability-deprecated)

This content is deprecated.

The MapReduce framework is deprecated from Talend 7.3 onwards. Use Talend Jobs for Apache Spark to accomplish your integration tasks.

## Basic settings

| Schema and Edit<br>Schema | A schema is a row description. It defines the number of fields<br>(columns) to be processed and passed on to the next component. When you create a Spark<br>Job, avoid the reserved word line when naming the<br>fields.<br><br>Click Edit<br>schema to make changes to the schema. If the current schema is of the Repository type, three options are available:<br><br><ul> <li> <p> <span>View schema</span>: choose this                option to view the schema only.</p> </li> <li> <p> <span>Change to built-in property</span>:                choose this option to change the schema to <span>Built-in</span> for local changes.</p> </li> <li> <p> <span>Update repository connection</span>:                choose this option to change the schema stored in the repository and decide whether                to propagate the changes to all the Jobs upon completion. If you just want to                propagate the changes to the current Job, you can select <span>No</span> upon completion and choose this schema metadata                again in the <span>Repository Content</span>                window.</p> </li> </ul> |
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| Sampling fraction | Enter the sample size ratio to the data being processed. For<br>example, enter *0.1*, then the<br>ratio of the sampled data to the total data being processed is<br>10%. |
| Use a seed for random number generator | Enter a positive seed number (the starting number for a random<br>sequence of generated numbers) so that the same sample is<br>reproducible. |

## Global Variables

| Global Variables | ERROR\_MESSAGE: the error message generated by the component when an<br>error occurs. This is an After variable and it returns a string. This variable functions<br>only if the Die on error check box<br>is cleared, if the component has this check<br>box.<br><br>A Flow variable functions during the execution of a component<br>while an After variable functions after the execution of the component.<br><br>To fill up a field or expression with a<br>variable, press Ctrl + Space to<br>access the variable list and choose the variable to use from it.<br><br>For further information about variables, see *Talend Studio*<br>*User Guide*. |
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## Usage

| **Usage rule** | This component is an intermediate component that passes sampled datasets to the<br>component that follows. This sampling proceeds without<br>replacement.<br><br>Note that the knowledge of statistics and sampling is<br>required.<br><br>This component, along with the MapReduce family it belongs to, appears only when you are<br>creating a Map/Reduce Job.<br><br>Note that in this documentation, unless otherwise<br>explicitly stated, a scenario presents only Standard Jobs,<br>that is to say traditional<br>Talend<br>data integration Jobs, and non Map/Reduce Jobs. |
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| Hadoop Connection | You need to use the Hadoop Configuration tab in the<br>Run view to define the connection to a given Hadoop<br>distribution for the whole Job.<br><br>This connection is effective on a per-Job basis. |