Associating a table with more than just one other table

Need Help
1

Hey, how can I associate a table with more than just one other table, when the other tables need to use the same foreignKey.

e.g.:

class FramesTable extends Table
{

    $this->belongsTo('Articles', [
        'foreignKey' => 'item_id',
        'joinType' => 'INNER',
    ]);
    
     $this->belongsTo('Entities', [
        'foreignKey' => 'item_id',
         'joinType' => 'INNER',
    ]);

best,

2

Hmm. That sounds a bit fuzzy to me. A future programmer (or even your future self) might curse you for this choice :slight_smile:

What are you actually trying to accomplish with this schema?

3

well lets say you have a RatingsTable plus functions to rate Cars/Boats and you want to use the same table/functions with your Cars and Boats Table/Controller… e.g.: with ajax…

class RatingsTable extends Table
{

    $this->belongsTo('Cars', [
        'foreignKey' => 'item_id',
        'joinType' => 'INNER',
  
    ]);
    
     $this->belongsTo('Boats', [
        'foreignKey' => 'item_id',
         'joinType' => 'INNER',
    ]);
4

I’m probably missing a lot of nuance here but:

In this example, I would see no reason to create the Associations in RatingsTable. My reason being, Ratings serve as enriching/explanatory data for some item/product (Car or Boat). I can’t envision a case where I would have a Rating record independent of any other record, and have a need to find the associated ‘whatever’.

It’s technically possible to ‘need’ this in the case of a generic view or index page for a Rating. But in terms of the meaningful presentation of data in some UI or in a situation where I was gathering data for some programming reason, I don’t ever see getting the data from the Ratings side of the relationship.

As far as I know your could have this code with no problem:

//in class CarsTable {
    $this->hasOne('Ratings', [
        'foreignKey' => 'rating_id',
   ]);

//in BoatsTable
     $this->hasOne('Ratings', [
        'foreignKey' => 'rating_id',
    ]);
5

your code was already part of mine but i need the belongsTo’s in the RatingsTable as well, because otherwise it will not be possible to access the Rating through the $boats object…
e.g.: $boats->rating->average…

maybe i will have to write a plugin for the ratings, because i want to reuse the code to calculate average values etc…

6

I don’t believe that’s true. Have you tried without the associations in Ratings?

Though I can’t lay my hands on code to 100% verify that right this second, I believe there have been several times where I hand created an association definition on one table without the inverse relationships on the other table and everything worked fine.

Your query would be from the Cars or Boats side

$query = $this->VehicleTable
   ->find()
   ->contain(['Ratings'])
   ->where(['some' => 'condition']);

The association definitions in Ratings should only be needed if you wanted to query from that table and include one of the vehicle classes.

1 Like
7

To be clear, ratings table would have id and any rating data fields but no record of what it belongs to; no foreign key field.

Your vehicle class tables would have id, rating_id and other needed columns.