Adding Columns
Follow these steps to add a Column node and configure it:
Drag and drop the column node from the Operations palette and drop it in the canvas. By default the name of the Column node is “Columns”. To modify the name, click on the name and provide a new name.
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Move the column node towards the dataset node on the canvas. You will see a connector appear between the two nodes, indicating a successful connection. |
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The Column configuration pane is displayed below the Canvas. If the configuration pane is not displayed, make sure the column node is selected in the canvas. All the columns of the dataset are included by default, By clicking on the check box to the right of each column, columns can be selected/deselected (included/excluded) from displaying in the flow. |
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By default, the name of the column is retained from the dataset it was selected from. You can change the display name by clicking on the name displayed in the Column Name field and providing a new name. |
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The Column Type can be changed by clicking on the type displayed in the Type field. |
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Click on the Source column to open the Expression Editor. Using the Expression Editor, you can view and edit the expression of the column. |
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Click on the helper tools icon displayed on the top left corner of the expression editor A list of expressions will be displayed. Click on the function name to display a help window with the syntax of the selected function. Refer to the chapter SQL Functions in the TDV Reference Guide for a complete list of the supported SQL functions with syntax help and examples. |
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A preview of the dataset is displayed to the right of the Column Configuration pane. The order of the displayed columns can be altered by moving the column header. |
Features and Limitations of the Column Operation
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The Column operation can have only one input and one output. |
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This operation can be added after any operation except the Publish operation. |