entry1|entry2|entry3|entry4|entry5|
entry6|entry7|entry8|entry9|entry10|
entry11|entry12|entry13|entry14|entry15|

##</code><code>##

open (DATA, "data.dat")
@data = <DATA>;
close (DATA);

foreach $item (@data)
{
    @elements = split (/\|/, $item);
    # do your comparisons to each item in @elements here
}