Chapter 9 Data Transformations Basics

Define and detail each task

You define and detail each data transformation task in a Data Transformation Diagram.

In order to create this diagram, you have to create a task in the Data Transformation Tasks tab of the transformation process property sheet. You select the new task and click the Open Diagram tool in the toolbar to navigate to the corresponding diagram. The task acts as a container for the corresponding diagram.

The data transformation diagram shows how data is extracted from data inputs, transformed by actions and loaded into data outputs.

Data is represented by data structure columns, that come from data inputs and transit using data flows from one step to another with transformations until they meet business needs and are therefore mapped to the target object structure columns.

In the diagram, you create data inputs, data outputs and actions. For data inputs and outputs, you can drag a source or a target data store from the browser and drop it in the data transformation diagram.

In each of the data input and data output property sheet, you define the data connection to identify from where the data is extracted or loaded.

You then define data structure columns for a data input and link the data input to an action using a data flow. This initializes the Data Structure Columns tab of the action. For more information see the "Data Structure Columns" section in the "Building Data Transformation Diagrams" chapter.

You can keep on defining data structure columns for actions in any of the following ways:

• Use the Data Structure Columns tabs in the action property sheet.
• Use the Data Structure Mapping Editor from the contextual menu of the action or using the Open Mapping Editor tool on the Data Structure Columns tab in the action property sheet. For more information see the "Data Structure Mapping Editor" section in the "Building Data Transformation Diagrams" chapter.

You then have to define the transformation rules, such as scripts or criteria for example when required.

At last, you link the last action to a data output using a data flow. This initializes the Data Structure Columns tab of the data output. You need to define the target object in which the data will be loaded in the Target Object list on the General tab of the data output property sheet.

For more information about data transformation diagrams, see the "Building Data Transformation Diagrams" chapter.

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