Thread: string functions

I have studied the Users Lounge and links off of it, looking for a place
where PG users are sharing extended functions they have created for PG.

In particular I am looking for string functions such as being able to
specify a start point for finding a substring within a string. The existing
PGSQL function position(substring,string) nor strpos(string,substring) have
the option of specifying a start point for the search.

Also I am looking for a function to reverse a string, so that for example
reverse("april") returns "lirpa"

Can anyone point me to an area where users are sharing functions they
created, especially the ones I'm looking for? At this point I'm not able to
write one for myself. I am stuck using Cold Fusion which does include the
functions I need, but is so slow at it that it times out before completing
the update to all of my 250,000 records.

Thank you,

- April

Took me 10 min to complete

CREATE FUNCTION substr_start(varchar,varchar,int4) RETURNS varchar AS '
DECLARE
     original alias for $1;
     substring alias for $2;
     startpoint alias for $3;
     return_str varchar;
BEGIN
  return strpos(substr(original,startpoint,length(original)),substring);
END;'
LANGUAGE 'plpgsql'


CREATE FUNCTION reverse_str(varchar) RETURNS varchar AS '
DECLARE
       original alias for $1;
       reverse_str varchar;
       i int4;
BEGIN
 reverse_str = '''';
 FOR i IN REVERSE LENGTH(original)..1 LOOP
  reverse_str = reverse_str || substr(original,i,1);
 END LOOP;
 return reverse_str;
END;'
LANGUAGE 'plpgsql';



http://www.pgexplorer.com
GUI postgresql tool


----- Original Message -----
From: "April L" <april@i-netco.com>
To: <pgsql-novice@postgresql.org>
Sent: Sunday, April 14, 2002 7:02 PM
Subject: [NOVICE] string functions


> I have studied the Users Lounge and links off of it, looking for a place
> where PG users are sharing extended functions they have created for PG.
>
> In particular I am looking for string functions such as being able to
> specify a start point for finding a substring within a string. The
existing
> PGSQL function position(substring,string) nor strpos(string,substring)
have
> the option of specifying a start point for the search.
>
> Also I am looking for a function to reverse a string, so that for example
> reverse("april") returns "lirpa"
>
> Can anyone point me to an area where users are sharing functions they
> created, especially the ones I'm looking for? At this point I'm not able
to
> write one for myself. I am stuck using Cold Fusion which does include the
> functions I need, but is so slow at it that it times out before completing
> the update to all of my 250,000 records.
>
> Thank you,
>
> - April
>
>
>
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