CakePHP database queries DISTINCT / GROUP BY error - php

Question

In my CakePHP model I'm trying to get some data from my table.
I tried using DISTINCT but it seems like using DISTINCT doesn't change the query results.
I can see many rows that has the same nick
with 'DISTINCT Mytable.nick'
$this->Mytable->find('all',
array(
'fields'=> array(
'DISTINCT Mytable.nick',
'Mytable.age', 'Mytable.location',
),
'conditions' => array('Mytable.id >=' => 1, 'Mytable.id <=' => 100),
'order' => array('Mytable.id DESC')
));
with 'group Mytable.nick'
$this->Mytable->find('all',
array(
'fields'=> array(
'Mytable.nick',
'Mytable.age', 'Mytable.location',
),
'conditions' => array('Mytable.id >=' => 1, 'Mytable.id <=' => 100),
'group' => 'Mytable.nick',
'order' => array('Mytable.id DESC')
));
with 'Mytable.nick'
$this->Mytable->find('all',
array(
'fields'=> array(
'Mytable.nick',
'Mytable.age', 'Mytable.location',
),
'conditions' => array('Mytable.id >=' => 1, 'Mytable.id <=' => 100),
'order' => array('Mytable.id DESC')
));
Edit: It seems like even CakePHP 2.1 can't use DISTINCT option. When I tried "GROUP BY" it solved my issue. But as you can see from my query I need to order results with Mytable.id descended. When I use GROUP BY, when Mysql finds relevant row, it doesn't take others. For example.
id=1, nick=mike, age=38, location=uk
id=2, nick=albert, age=60, location=usa
id=3, nick=ash, age=42, location=uk
id=4, nick=albert, age=60, location=new_zelland
When I use group Mytable.nick, I don't see 4th row in my results, I see 2nd row. Because when mysql saw "albert" second time, it doesn't put it into my results. But I need latest "albert" result. Is it not possible?
Edit2: It seems like order by/group by conflict is a common problem. I found some tips in this question. But it gives solution for native Mysql queries. I need a solution for CakePHP type queries.

Answer 1

Not clear on why you want to group by nick and order by id. Do you intend to use an aggregate function like COUNT() to see how many occurrences of the same nick there are? In short you overall goal still is not clear to me. Might be worth being aware of the HAVING MySQL keyword.
Updated: Ok, that makes more sense. So you need to use a sub select on the condition or perhaps express that as a join. I'll try and show an example using the sub select in the WHERE clause.
/* select last occurrence for each nick (if you need one for each location )*/
SELECT nick, age, location
FROM myTable t1
WHERE id =
(SELECT MAX(id)
FROM myTable t1
WHERE t1.nick = t2.nick);
Would think something like this would work:
$this->Mytable->find('all',
array(
'fields'=> array(
'Mytable.nick',
'Mytable.age', 'Mytable.location',
),
'conditions' => array('Mytable.id =' => '(SELECT MAX(id) FROM myTable t2 WHERE myTable.nick = t2.nick)', 'Mytable.id <=' => 100)
));