I have two files
The first file should remain as how it is and
If the 4th column of the second file is occurs in the 7th column of the first file -> write that row of the second file to the end of corresponding row of the first file
Could you please help on that.
I suggest you http://stackoverflow.com/ for this kind of technical questions.
For other hand, when you ask this type of questions, it is highly recommended to add an example of input(s) and desired output file(s).
What have you tried?
can you provide a few line of your 2 files