Hello jzelkowsz and welcome to the monastery and to the wonderful world of Perl!

As you already got useful answers I propose you a short version(pay attention to windows double quotes!):

perl -F"," -lane "push @{$h{$F[0]}},$F[1]}{print map{$_.'|'.(join',',@
+{$h{$_}}).qq(\n)}keys %h" data.txt

20155505|YOUSLAV,YURT,TENWIMPL
20102741|WEDLOFOU,YOUSLAV,YURT,KUPLYSO,TENWIMPL
20011541|YOUSLAV,TENWIMPL
20011271|YOUSLAV,WUMARTHE
20147155|YOUSLAV,KUPLYSO,FRIMA
20055111|YOUSLAV,YURT,TENWIMPL

[download]

See perlrun to get all these perl switches explained, but use -MO=Deparse to see the oneliner exploded and more readable (the curly braces in $F[1]}{print are a trick called esquimo greeting;):

perl -MO=Deparse -F"," -lane "push @{$h{$F[0]}},$F[1]}{print map{$_.'|
+'.(join',',@{$h{$_}}).qq(\n)}keys %h"

BEGIN { $/ = "\n"; $\ = "\n"; }
LINE: while (defined($_ = <ARGV>)) {
    chomp $_;
    our(@F) = split(/,/, $_, 0);
    push @{$h{$F[0]};}, $F[1];
}
{
    print map({$_ . '|' . join(',', @{$h{$_};}) . "\n";} keys %h);
}
-e syntax OK

[download]

L*

There are no rules, there are no thumbs..
Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.

In reply to Re: How do I remove duplicate numeric elements of an array and preserve alphabetic elements? -- oneliner by Discipulus
in thread How do I remove duplicate numeric elements of an array and preserve alphabetic elements? by jzelkowsz

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