When you write to flat file targets, you can configure the Integration Service to write the column header information. When you enable the Output Metadata For Flat File Target option, the Integration Service writes column headers to flat file targets. It writes the target definition port names to the flat file target in the first line, starting with the # symbol. By default, this option is disabled.

When writing to fixed-width files, the Integration Service truncates the target definition port name if it is longer than the column width.

For example, you have a flat file target definition with the following structure:

The column width for ITEM_ID is six. When you enable the Output Metadata For Flat File Target option, the Integration Service writes the following text to a flat file: