tJavaFlex

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. When you create a Spark Job, avoid the reserved word line when naming the fields.

  Click Sync columns to retrieve the schema from the previous component in the Job.

  This component offers the advantage of the dynamic schema feature. This allows you to retrieve unknown columns from source files or to copy batches of columns from a source without mapping each column individually. For further information about dynamic schemas, see Dynamic schema.

  This dynamic schema feature is designed for the purpose of retrieving unknown columns of a table and is recommended to be used for this purpose only; it is not recommended for the use of creating tables.

• Built-In: You create and store the schema locally for this component only.

• Repository: You have already created the schema and stored it in the Repository. You can reuse it in various projects and Job designs.

  When the schema to be reused has default values that are integers or functions, ensure that these default values are not enclosed within quotation marks. If they are, you must remove the quotation marks manually.

  For more information, see Retrieving table schemas.

• 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.

Data Auto Propagate

Select this check box to automatically propagate the data to the component that follows.

Start code

Enter the Java code that will be called during the initialization phase.

Main code

Enter the Java code to be applied for each line in the data flow.

End code

Enter the Java code that will be called during the closing phase.

Import

Enter the Java code that helps to import, if necessary, external libraries used in the Main code box of the Basic settings view.

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

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 more information about variables, see Using contexts and variables.

Usage rule

You can use this component as a start, intermediate or output component. You can as well use it as a one-component subJob.

Limitation

You should know the Java language.