Hello
I have statements (highly simplified just to get
the point across) like
select a,b,c from a where d=2 order by e limit 10;
Now I think that because of "order by" the above query
already "knows" the result of the below query
select count(*) from a where d=2;
The point is that I want to know the total number
of matches and I also want to use "limit". And
I don't want to do two queries.
If it's impossible I would like to know whether
it costs the same to PG if I use it with or
without limit.
If I use DBI and simplified queries look like
$s=$dbh->prepare('select a,b,c from a where d=2 order by e ');
$s->execute();
I get the total number of rows by
$n=$s->rows;
I then use perl to implement "limit"
Thanks in advance for any hints
