tSetDynamicSchema - 6.1

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tSetDynamicSchema properties

Component family

Custom Code



tSetDynamicSchema allows you to set a dynamic schema that can be reused by components in the subsequent subjob or subjobs to retrieve data from unknown columns.


tSetDynamicSchema is used to create a dynamic schema to allow components that are unable to guess the structure of the data being handled based on field separators, such as tFileInputPositional and tFileOutputPositional, to retrieve data from unknown columns.

Basic settings

Schema and Edit schema

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

Since version 5.6, both the Built-In mode and the Repository mode are available in any of the Talend solutions.



Built-In: You create and store the schema locally for this component only. Related topic: see Talend Studio User Guide.



Repository: You have already created the schema and stored it in the Repository. You can reuse it in various projects and Job designs. Related topic: see Talend Studio User Guide.


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.

 Sync columnsClick to synchronize the output file schema with the input file schema. The Sync function is available only when the component is linked with an input component using a Row connection.

This table contains two columns.

Property: Property of the schema entry: ColumnName, DBName, Type, DBType, Length, Precision, Nullable, or Key.

Value: Value assigned to this property.

Advanced settings

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

DYNAMIC: the last row of the data retrieved using the defined dynamic schema. This is an After variable and it returns a dynamic.

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 check box is cleared, if the component has this check box.

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 further information about variables, see Talend Studio User Guide.


This component is generally used as the end component in a subjob.


If you are using a subscription-based version of the Studio, the activity of this component can be logged using the log4j feature. For more information on this feature, see Talend Studio User Guide.

For more information on the log4j logging levels, see the Apache documentation at http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/Level.html.


This component always requires an input component to defines the data structure to set into a dynamic schema.


To work with tSetDynamicSchema, components should have the option of Use existing dynamic, which allows you to select the tSetDynamicSchema component from the list.

Related scenario

For a related scenario that uses the tSetDynamicSchema component, see Scenario 2: Handling a positional file based on a dynamic schema of the tFileInputPositional component.