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Data Model Questions /

Moderators: martimiz, Sean, Ed, biapar, Willr, Ingo, swaiba

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8 Posts   1716 Views

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Stefdv

Community Member, 110 Posts

21 April 2011 at 4:08am

Hello,

I have a question about Database optimalisation.
I have a Dog (DO) that has a father and a mother. At the moment i have about 200 Dogs in my database, since every dog has a father and a mother i can build a pedigree...I have 2 options for this ( both working, that's not the problem )

option 1) In my template;

<% control MyDad %>
$PedigreeName
         <% control MyDad %>
          $PedigreeName
                 <% control MyDad %>
                 $PedigreeName
         etc.etc.
                <% end_control %>
       <% end_control %>
 <% end_control %>

Option 2 ) create functions in my DataObject Dog

function getMyDad(){
$father = dataObject::get_by_id('Dog', $this->MyFatherID); 
		return $father;
   	}

function getFather3()
{
	$father3 = dataobject::get_by_id('Dog',$this->MyDad->MyFatherID);
	return $father3;
}

function getFather7()
{
	$father7 = dataObject::get_by_id('Dog',$this->Father3->MyFatherID);
	return $father7;
}
etc etc.

Then i can use those in my template, filling out my table.
What is the most effective way to do this?

One other issue i'm having is that i need to compare every father/mother if they are already in the table since that could be inbred..
ps @Swaiba; Yes yes, still working on the thing ;)

Avatar
rob.s

Community Member, 78 Posts

21 April 2011 at 6:36pm

Hi Stefdv,

would it not be easier when having the ancestors as named relations ?

class Dog extends DataObject {
  static $db = array('Name' => 'Varchar');

  static $has_one = array(
    'Father' => 'Dog',
    'Mother' => 'Dog'
  );
}

When retrieving the ancestors you can use the simple notation:

$father= $myDog->Father();
$grand_father = $myDog->Father()->Father();

greets, Rob

Avatar
Stefdv

Community Member, 110 Posts

21 April 2011 at 9:48pm

Rob,
tx for replying

Well, i have


static $has_one = array (
'MyFather' = 'Father',
"MyMother' = 'Mother');

Where Father / Mother is a DO that reverts to Dog.
The way you put it looks more logic. I will try that...I'm in a learning curve and most of the times i do it the hard way :(

Can i repeat

 $grand_father = $myDog->Father()->Father(); 
endlessly ? like GreatGreatGrandFather would be
$greatgreatgrand_father = $myDog->Father()->Father()->Father()->Father();

Anyway of comparing every dog i use in my template pedigree?

Avatar
rob.s

Community Member, 78 Posts

21 April 2011 at 10:30pm

hmm,
i cannot say why it's necessary to store parents in separate classes ....
But yes, you can use the Parent() accessor endless - as long there are parents

E.g.
When a dog has only 1 parent and you use
$dog->Parent()->Parent()->Parent() you will get an error because, the second Parent() call does not return a DataObject(set)

Avatar
Stefdv

Community Member, 110 Posts

21 April 2011 at 10:37pm

No, i don't know why they have to be a seperate class also :) I'm gonna do it your way.

Can't i supress the error with

<% If Grandfather %>
$grandfather.$PedigreeName
<% end_if %>

?

Avatar
rob.s

Community Member, 78 Posts

21 April 2011 at 10:41pm

Edited: 21/04/2011 10:44pm

yep - right

in your model:

function Grandfather() {
  if( $dad = $this->Father() ) {
    return $dad->Father();
  } else {
    return false;
  }
}

in your template:

<% if Grandfather %>
  <% control Grandfather %>
    $Name
  <% end_control %>
<% end_if %>

Avatar
Stefdv

Community Member, 110 Posts

21 April 2011 at 11:13pm

Okay,

But i was planning to use the If statement only in my template. Why should i use that in my function also?

Sorry for asking, i'm just learning

Avatar
swaiba

Forum Moderator, 1899 Posts

22 April 2011 at 7:10am

Hi Stefdv,

I believe it's best to do the if to return a 'null' instead of an empty, but not null ComponentSet object. Return something instead of nothing would pass the if in the template - when you are not expecting it to.

ps @Swaiba; Yes yes, still working on the thing ;)

how many projects ever end? :)