Re: getLinks from an M-N jointure : multiple records ?

On 7/19/05, David Alia <david.alia@gmail.com> wrote: > Oups. > This code works... almost (I tried with both first and second example). Try the third one. That one makes use of selectAdd(). > > I get the right number of lines (corresponding to the right number of > groups) but, they are empty... > > it seems that it doesn't find $group->name in the first case, > $group_connect->name in the second case. > > just to be sure, if my fields are PERSON.name and GROUP.name, which > "name" do you speak about ? (to me it is GROUP.name). > > Thank for your help... > David > > -----Message d'origine----- > De : Justin Patrin [mailto:papercrane@gmail.com] > Envoyé : lundi 18 juillet 2005 18:52 > À : David Alia > Cc : pear-general@lists.php.net > Objet : Re: [PEAR] getLinks from an M-N jointure : multiple records ? > > [snip] > > This is what is called a crossLink in the DB_DataObject_FormBuilder > package. There is no way in DB_DataObject to get these connections > with a single funciton call like getLink. However this is still very > easy. I'm actually very surprised at how often this question seems to > be asked... > > $person =& DB_DataObject::factory('person'); $person->get(13); > $group_connect =& DB_DataObject::factory('persgroup'); > $group_connect->personID = $person->ID; > if ($group_connect->find()) { > while ($group_connect->fetch()) { > $group =& $group_connect->getLink('groupID'); > echo $group->name.'<br/>'; > } > } > > Or alternatively, you can use joinAdd to reduce your queries: > > $person =& DB_DataObject::factory('person'); $person->get(13); > $group_connect =& DB_DataObject::factory('persgroup'); > $group_connect->personID = $person->ID; > $group =& DB_DataObject::factory('group'); > $group_connect->joinAdd($group); if ($group_connect->find()) { > while ($group_connect->fetch()) { > echo $group_connect->name.'<br/>'; > } > } > > Or even further: > > $group_connect =& DB_DataObject::factory('persgroup'); > $person =& DB_DataObject::factory('person'); $person->ID = 13; > $group_connect->joinAdd($person); $group =& > DB_DataObject::factory('group'); $group_connect->joinAdd($group); > $group_connect->selectAdd(); //technically these should be quoted with > DB::quoteIdentifier() $group_connect->selectAdd('group.name'); > if ($group_connect->find()) { > while ($group_connect->fetch()) { > echo $group_connect->name.'<br/>'; > } > } > -- Justin Patrin