# tFileOutputARFF Writes an ARFF file that holds data organized according to the defined schema. ## tFileOutputARFF Standard properties These properties are used to configure tFileOutputARFF running in the Standard Job framework. The Standard tFileOutputARFF component belongs to the File family. The component in this framework is available in all Talend products. ## Basic settings | Properties | Description | | --- | --- | | Property type |

Either Built-in or Repository.
Built-in: No property data stored centrally.
Repository: Select the repository file where the properties are stored. The fields that follow are completed automatically using the data retrieved.

| | ![](https://help.qlik.com/talend/en-US/components/8.0/Resources/images/Save_Icon.png) | Click this icon to open a connection wizard and store the Excel
file connection parameters you set in the component Basic settings view.

For more information about setting up and storing file
connection parameters, see [Setting connection parameters](https://help.qlik.com/talend/r/en-US/8.0/studio-user-guide/setting-connection-parameters). | | File name | Name or path to the output file and/or the variable to be used.

For further information about how to define and use a variable in a Job, see [Using contexts and variables](https://help.qlik.com/talend/r/en-US/8.0/studio-user-guide/contexts-and-variables).

Information noteWarning: Use absolute path (instead of relative path) for
this field to avoid possible errors. | | Attribute Define | Displays the schema you defined in the Edit
schema dialog box.

Column: Name of the
column.

Type: Data type.

Pattern: Enter the data model
(pattern), if necessary. | | Relation | Enter the name of the relation. | | Append | Select this check box to add the new rows at the end of the
file. | | Schema and Edit
Schema |

A schema is a row description, it defines the number of fields to be processed and passed on to the next component. The schema is either Built-in or stored remotely in the Repository.

Click Edit schema to make changes to the schema. If the current schema is of the Repository type, three options are available:
- View schema: choose this option to view the schema only.
- Change to built-in property: choose this option to change the schema to Built-in for local changes.
- Update repository connection: 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 No upon completion and choose this schema metadata again in the Repository Content window.
Built-in: You can create the schema and store it locally for this component. For more information about a component schema in its Basic settings tab, see Basic settings tab.
Repository: You have already created and stored the schema in the Repository. You can reuse it in various projects and Job flowcharts. For more information about a component schema in its Basic settings tab, see Basic settings tab.

| | Create directory if not exists | This check box is selected by default. It creates a directory to
hold the output table if it does not exist. | ## Advanced settings | Properties | Description | | --- | --- | | Don't generate empty file | Select this check box if you do not want to generate empty
files. | | tStatCatcher Statistics | Select this check box to gather the Job processing metadata at a
Job level as well as at each component level. | ## Global Variables | Variables | Description | | --- | --- | | Global Variables | NB\_LINE: the number
of rows read by an input component or transferred to an output component. This is an
After variable and it returns an integer.

ERROR\_MESSAGE: the error message generated by the
component when an error occurs. This is an After variable and it returns a string. This
variable functions only if the Die on error checkbox is
cleared, if the component has this checkbox.

A Flow variable functions during the execution of a component
while an After variable functions after the execution of the component.

To fill up a field or expression with a variable, press Ctrl+Space to access the variable list and choose the variable to use from
it.

For more information about variables, see [Using contexts and variables](https://help.qlik.com/talend/r/en-US/8.0/studio-user-guide/contexts-and-variables). | ## Usage | Usage guidance | Description | | --- | --- | | **Usage rule** | Use this component along with a Row link to collect data from another component and
to re-write the data to an ARFF file. | | Dynamic settings | Click the [+] button to add a row in the
table and fill the Code field with a context variable
to choose your HDFS connection dynamically from multiple connections planned in your
Job. This feature is useful when you need to access files in different HDFS systems or
different distributions, especially when you are working in an environment where you
cannot change your Job settings, for example, when your Job has to be deployed and
executed independent of *Talend Studio*.

The Dynamic settings table is
available only when the Use an existing
connection check box is selected in the Basic settings view. Once a dynamic parameter is
defined, the Component List box in the
Basic settings view becomes unusable.

For examples on using dynamic parameters, see [Reading data from databases through
context-based dynamic connections](https://help.qlik.com/talend/r/en-US/8.0/components/defining-context-groups/reading-data-from-databases-through-context-based-dynamic-connections) and [Reading data from different MySQL databases
using dynamically loaded connection parameters](https://help.qlik.com/talend/r/en-US/8.0/components/context/reading-data-from-different-mysql-databases-using-dynamically-loaded-connection-parameters). For more information on
Dynamic settings and context variables, see
[Dynamic schema](https://help.qlik.com/talend/r/en-US/8.0/studio-user-guide/dynamic-schema) and [Creating a context group and define context
variables in it](https://help.qlik.com/talend/r/en-US/8.0/studio-user-guide/creating-context-group-and-define-context-variables-in-it). | | Connections | Outgoing links (from this component to another):

Row: Main.

Trigger: On Subjob Ok; On Subjob
Error; Run if.

Incoming links (from one component to this one):

Row: Main; Reject;
Iterate.

Trigger: On Subjob Ok; On Subjob
Error; Run if; On Component Ok; On Component Error; Synchronize;
Parallelize.

For further information regarding connections, see [Using connections in a Job](https://help.qlik.com/talend/r/en-US/8.0/studio-user-guide/using-connections-in-job). | | Limitation | Due to license incompatibility, one or more JARs required to use this component
are not provided. You can install the missing JARs for this particular component by
clicking the Install button on the Component tab view. You can also find out and add all missing
JARs easily on the Modules tab in the Integration perspective of Talend Studio. For
details, see [Installing external modules](https://help.qlik.com/talend/r/en-US/8.0/studio-user-guide/installing-external-modules). |