File List is a concept that provides you with an easier way to merge the data and load it into the target. As the name suggests, it is specifically related to flat files. This is an indirect way of passing the source file. We saw earlier that we can define the source path and the source file name under the mapping tab in the session task. There is another property in the session task called the Source File type, where you can select the Direct or Indirect option, as shown in the following screenshot:

When we select Source filetype as Direct, Informatica directly goes to the defined Source file directory path and extracts the data from the filename defined in the Source filename option. When you select Source filetype as Indirect, Informatica reads the data from the file mentioned indirectly. Let's look at an example to understand this concept.

Consider that you have been provided with three source files with the same structure but different data. The names of...