String functions like split() and join() in plpgsql

Hi,

I'm writing a trigger to change the third field in a varchar record. (it's
an SOA field from DNS) and I can do it in plperl but since it needs to be a
trigger I have to do it in plpgsql (or other right?).

In perl it's as simple as:
// assuming $soa = 'ns1.domain.com hostmaster.domain.com 104249825 10800
3600 604000 86400';
@x =  split(/ /, $soa); $x[2] = time(); join(' ', @x);

Any ideas on how I can create a trigger to change the third field to now()?

Can I use perl as a trigger?

Thanks in advance,
davidu

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