Basically what this is is a logfile that has alerts from a program.
The entries get dropped into a file continually. But some entries have the same date, transaction ID, location, alert code and keep getting dropped in over and over (like until the problem is fixed)

The awk filter is to create a 2nd file that just adds new messages if they are not the same date, ID, location, code, and run on a continual basis filtering these out.