Re: problems with a select query in informix

On 5 Jul, stephan.schoell@chhos.mail.abb.com wrote: > > > Interesting! I've had the same problem with mysql on apache/cobalt linux. the > mysql function max() returned 0 no matter what data was in the table. Locally on > my Win95/apache/mysql system, everything worked fine. My solution (also very > ugly and slow but...): I made a loop through all the rows and looked for the max > value in my php script. > > $max=0; > while ($row=mysql_fetch_array(......)) { > if ($max<$row['whatever_value']) {$max=$row['whatever_value']} > } > > I'm sure, there are better solutions, either in mysql or in php. > > --Steff > webmaster@posh.ch > www.posh.ch > > hello, I got a problem, and I think it has to do with my low knowledge about > how php treats arrays. > What I do is this: > > 1) I do an insert to the articulo table with some data. > > 2) I run the hack below to read the biggest integer in articulo.a_id for > later use. articulo.a_id is a SERIAL. > > $q_id_identi=ifx_query("SELECT MAX (a_id) FROM articulo",$conn_id); > $q_ar_identi=ifx_fetch_row($q_id_identi); > echo(sprintf("<br> %d <br>",$q_ar_identi[a_id])); > > The problem is that the echo you see above give me 0. But if I make the query > directly in dbaccess (an informix program which lets throw querys) and the > answer is diferent. > > What am I doing wrong??? > You may find it useful to assign the MAX value to an alias, and then get the value of the alias. For mysql, something like this: $result = mysql_db_query($database,"SELECT MAX(a_id) AS mavxal FROM articulo",$conn_id); $row = mysql_fetch_array($result); $biggestnum = $row["maxval"]; Cheers -- David Robley | WEBMASTER & Mail List Admin RESEARCH CENTRE FOR INJURY STUDIES | http://www.nisu.flinders.edu.au/ AusEinet | http://auseinet.flinders.edu.au/ Flinders University, ADELAIDE, SOUTH AUSTRALIA