You can configure a flat file data object to accommodate changes to source metadata at run time. The Data Integration Service can read data from a flat file where the number or order of the columns is different from that of the columns in the flat file physical data object.
For example, you have a mapping whose source is provided by another department. The department that provides the source cannot guarantee the order of columns in the source file. Sometimes, the department might change the columns in the file or contain additional columns. You can configure the flat file data object to accept changes in the source metadata at run time.
You can generate the run-time column names automatically from any row in the source, from the flat file header, or from the control file.
You can use input rules to project the run-time columns from the Read transformation based on the flat file data object to the next transformation in the mapping.
You can configure the Read transformation data object property to select
At runtime, get data object columns from the data source
on the Data Object tab. After you configure the property, the options in the flat file data object determine how the Data Integration Service processes the data.