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Export Column Transformation

Applies to: SQL Server SSIS Integration Runtime in Azure Data Factory

The Export Column transformation reads data in a data flow and inserts the data into a file. For example, if the data flow contains product information, such as a picture of each product, you could use the Export Column transformation to save the images to files.

Append and Truncate Options

The following table describes how the settings for the append and truncate options affect results.

Append Truncate File exists Results
False False No The transformation creates a new file and writes the data to the file.
True False No The transformation creates a new file and writes the data to the file.
False True No The transformation creates a new file and writes the data to the file.
True True No The transformation fails design time validation. It is not valid to set both properties to true.
False False Yes A run-time error occurs. The file exists, but the transformation cannot write to it.
False True Yes The transformation deletes and re-creates the file and writes the data to the file.
True False Yes The transformation opens the file and writes the data at the end of the file.
True True Yes The transformation fails design time validation. It is not valid to set both properties to true.

Configuration of the Export Column Transformation

You can configure the Export Column transformation in the following ways:

  • Specify the data columns and the columns that contain the path of files to which to write the data.

  • Specify whether the data-insertion operation appends or truncates existing files.

  • Specify whether a byte-order mark (BOM) is written to the file.

    Note

    A BOM is written only when the data is not appended to an existing file and the data has the DT_NTEXT data type.

The transformation uses pairs of input columns: One column contains a file name, and the other column contains data. Each row in the data set can specify a different file. As the transformation processes a row, the data is inserted into the specified file. At run time, the transformation creates the files, if they do not already exist, and then the transformation writes the data to the files. The data to be written must have a DT_TEXT, DT_NTEXT, or DT_IMAGE data type. For more information, see Integration Services Data Types.

This transformation has one input, one output, and one error output.

You can set properties through SSIS Designer or programmatically.

The Advanced Editor dialog box reflects the properties that can be set programmatically. For more information about the properties that you can set in the Advanced Editor dialog box or programmatically, click one of the following topics:

For more information about how to set properties, see Set the Properties of a Data Flow Component.

Export Column Transformation Editor (Columns Page)

Use the Columns page of the Export Column Transformation Editor dialog box to specify columns in the data flow to extract to files. You can specify whether the Export Column transformation appends data to a file or overwrites an existing file.

Options

Extract Column
Select from the list of input columns that contain text or image data. All rows should have definitions for Extract Column and File Path Column.

File Path Column
Select from the list of input columns that contain file paths and file names. All rows should have definitions for Extract Column and File Path Column.

Allow Append
Specify whether the transformation appends data to existing files. The default is false.

Force Truncate
Specify whether the transformation deletes the contents of existing files before writing data. The default is false.

Write BOM
Specify whether to write a byte-order mark (BOM) to the file. A BOM is only written if the data has the DT_NTEXT or DT_WSTR data type and is not appended to an existing data file.

Export Column Transformation Editor (Error Output Page)

Use the Error Output page of the Export Column Transformation Editor dialog box to specify how to handle errors.

Options

Input/Output
View the name of the output. Click the name to expand the view to include columns.

Column
View the output columns that you selected on the Columns page of the Export Column Transformation Editor dialog box.

Error
Specify what you want to happen if an error occurs: ignore the failure, redirect the row, or fail the component.

Truncation
Specify what you want to happen if a truncation occurs: ignore the failure, redirect the row, or fail the component.

Description
View the description of the operation.

Set this value to selected cells
Specify what should happen to all the selected cells when an error or truncation occurs: ignore the failure, redirect the row, or fail the component.

Apply
Apply the error handling option to the selected cells.