Re: xpath() subquery for empty array

[Roy Walter <walt@xxxxxxxxxxxxxxxx>]

Sam Mason wrote:

On Sun, Jul 12, 2009 at 09:49:15PM +0100, Roy Walter wrote:
  

Where exactly does that fit in terms of my original query, i.e.:

   SELECT x
   FROM (SELECT xpath('//entry[contains(p, ''searchtext'')]/@*', docxml)
   AS x FROM docs) AS y WHERE x <> [test for empty array?????????]
    

Something like the following should do the right thing:

  SELECT x FROM (
    SELECT xpath('//entry[contains(p, ''searchtext'')]/@*', docxml) AS x
    FROM docs) AS y
  WHERE array_upper(x, 1) > 0;
  

Thank you, works just fine. I thought it was more complicated than that :-)

-- Roy