Hmm, not really clear on what you've got here but: 
while (<DATA>) {
    chomp;
    my ($userid, $password, $net_service_name) 
             = m#'?([^@/']+)?(/[^@/']+)?(@[^@/']+)?'?#;
    print "]]$_\[\[ 
  \tis parsed as \[$userid] \[$password] [$net_service_name]\n"
}   # while 

__DATA__
>>SYS/change_on_install@prod1<< <SYS> 
</change_on_install> <@prod1> 
>>rman/rman@rcat<< 
<rman> </rman> <@rcat> 
>>SYS<< <SYS> <> <> >>/<< <> </> <> 
>>/fooey<< <> </fooey> <> 
>>/fooey@foobar<< 
<> </fooey> <@foobar> 
>>SYS@foobar<< 
<SYS> <> <@foobar> 
>>'simple/fooey@foobar'<< 
<simple> </fooey> <@foobar>

[download]
I get a different result, seems you might want to consider white space, for one thing. That's not allowed, right? Are the pointy brackets legit Oracle chars?

a

In reply to Re: Parsing an Oracle connect string by a
in thread Parsing an Oracle connect string by fbicknel

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