I have a sub in a Perl script that loops execution the following
statement:
SELECT url,name FROM links
And formats it like so:
<a href='$url'>$name</a><br>
A variable ($link_list) is in the loop, holding the concatenated last
statement with the new one.
I would rather do this with FUNCTIONS (and/or AGGREGATES).
So, I CREATEd a FUNCTION:
CREATE FUNCTION format_link(text,text)
RETURNS text AS ' return qq[<a href="http://www.domain.com/$_[0]"
class="body_link">$_[1]</a>];
' LANGUAGE 'plperl';
So in my Perl script, the SQL statement becomes:
SELECT format_link(url,name) FROM links
However, I still have to loop with Perl -- it would be nice to use an
AGGREGATE to do some of this for me.
I can create an AGGREGATE but from what I can tell, the format of the
sfunc can only have two parameters like so:
sfunc_name(type,type)
Where the first parameter is what was passed before, and the second
parameter is the 'new' info to do stuff to. Is it not possible to do
something similar to?:
sfunc_name(type,type,type)
So that I can pass the url and name to the AGGREGATE (so it can in turn
pass it to the sfunc)? Where the sfunc could be something like so:
CREATE FUNCTION link_agg (text,text,text)
RETURNS text AS ' return $_[0] . qq[<a href="http://www.domain.com/$_[0]"
class="body_link">$_[1]</a><br>];
' LANGUAGE 'plperl';
Because then I gain benefit of a stored procedure and cut the SQL in the
script down to:
SELECT link_agg(url,name) FROM link;
Which will return the entire list at once, instead of needing the script
to loop through multiple fetches.
...
Of course, I may be going about this in an entirely incorrect manner.
Telling me so, with a bit of direction, would also be greatly
appreciated.
BTW: I tried searching the archives, but there is a database error
("PQconnectPoll() -- connect() failed: Connection refused Is the
postmaster running (with -i) at 'db.hub.org' and accepting connections
on TCP/IP port 5439?"), just so someone knows.
Thanks In Advance,
Anthony Bouvier
