Re: Select and order by question

On 5/3/06, Andy Dunlop <andy(at)infocus(dot)co(dot)za> wrote:
>
> Hi - I have the following code:
>
> //show table of current events needing action
> $sSql = "SELECT id FROM crm_leads ";
> $sLeads = pg_exec($conn,$sSql);
> for($e=0;$e<pg_numrows($sLeads);$e++){
> $sSql = "SELECT * FROM crm_events WHERE crm_leads_id = ".pg_result($sLeads,$e,"id")." AND follow_up_action!='' ORDER BY follow_up_date asc limit 1";
> $sRes = pg_exec($conn,$sSql);
> $sHits = pg_numrows($sRes);
> if($sHits!=0){
> for($i=0;$i<$sHits;$i++){
> // generate the display here
> }
> }
>
> crm_leads is a parent with many crm_events as it's children.
> This code gives me the correct set of rows.
> My problem is that I want only the last row from crm_events (as per limit 1) but I want those rows sorted by follow_up_date. I guess I need to have the whole query in one select statement? But how?

select * from crm_leads l, crm_events e where l.id=e.crm_leads_id and
follow_up_action != '' ORDER BY follow_up_date ASC LIMIT 1;

Make sure crm_events crm_leads_id has an index on id and cram_leads id..

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