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

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

From

"David U."

Date:

14 January 2003, 00:29:12

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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world. Indeed, it is the only thing that ever has." --Margaret Mead

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

From

Tom Lane

Date:

14 January 2003, 00:39:54

"David U." <davidu@everydns.net> writes:
> 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?).

There's nothing to stop you from calling a plperl function from a
plpgsql trigger function.  If you've got complicated string-mashing
requirements, I'd certainly recommend coding them in plperl (or pltcl).

Someday someone should get around to implementing trigger support for
plperl, but in the meantime a two-layer approach seems like your answer.

            regards, tom lane

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

From

elein

Date:

15 January 2003, 23:56:55

Or try plpython.  You can write triggers in plpython directly.

--elein

On Monday 13 January 2003 18:39, Tom Lane wrote:
> "David U." <davidu@everydns.net> writes:
> > 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?).
>
> There's nothing to stop you from calling a plperl function from a
> plpgsql trigger function.  If you've got complicated string-mashing
> requirements, I'd certainly recommend coding them in plperl (or pltcl).
>
> Someday someone should get around to implementing trigger support for
> plperl, but in the meantime a two-layer approach seems like your answer.
>
>             regards, tom lane
>
> ---------------------------(end of broadcast)---------------------------
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