Graham Kennedy
Graham Kennedy

Reputation: 736

Unable to Get Eloquent to Automatically Create Joins

I would like to use built-in ORM functionality in Laravel's Eloquent ORM to automatically join the tournaments and countries tables together when running a query, and return the data set that includes tournament data as well as its associated country data.

That is, I want Eloquent to recognize the foreign key relationship automatically so that I can just run a query (e.g. Tournament:: with('Country')->all()) that will return the entire set of tournament and country data.

Query that I Would Like to Replicate in Eloquent

SELECT * FROM tournaments LEFT JOIN countries ON tournaments.country_id = countries.id

Expected Result in PHP

I expect to receive an array of Tournament objects (in PHP), where a single Tournament object would look like:

Failed attempts that I've made so far

I ran all of these attempts in a dummy controller method and output the result as a formatted string to the profiler.

Failed Attempt #1:

PHP code in the dummy controller:

$tournaments = Tournament::with('Country')->all();

Generates the following query:

SELECT * FROM `tournaments`

Attempt #1 returns:

An array containing Tournament objects that only include the columns in the tournaments table.

Failed Attempt #2

PHP code in the dummy controller:

$tournaments = Tournament::with('Country')->first();

Generates the following error:

SQLSTATE[42S22]: Column not found: 1054 Unknown column 'tournament_id' in 'where clause'

SQL: SELECT * FROM `countries` WHERE `tournament_id` IN (?)

Bindings: array (
0 => '1',
)

Other Failed Attempts

I've tried various combinations of naming conventions (e.g. columns, tables, etc.) to no avail. I've also tried creating the query in Fluent, which worked fine, but required me to specify the joins which is what I'm trying to avoid.

My Environment

Relationship Between Tables

Countries Table

CREATE TABLE `countries` (                                                                                                                                                                                                                 
`id` int(11) NOT NULL AUTO_INCREMENT,                                                                                                                                                                                                       
`code` varchar(4) NOT NULL,                                                                                                                                                                                                                 
`name` varchar(25) NOT NULL,                                                                                                                                                                                                                
`url` varchar(25) NOT NULL,                                                                                                                                                                                                                 
`created_at` datetime NOT NULL,                                                                                                                                                                                                             
`updated_at` datetime NOT NULL,                                                                                                                                                                                                            
PRIMARY KEY (`id`),                                                                                                                                                                                                                        
UNIQUE KEY `countries_code_unique` (`code`),                                                                                                                                                                                               
KEY `countries_url_index` (`url`)                                                                                                                                                                                                          
) ENGINE=InnoDB AUTO_INCREMENT=28 DEFAULT CHARSET=latin1

Tournaments Table

CREATE TABLE `tournaments` (                                                                                                                                                                                                             
`id` int(11) NOT NULL AUTO_INCREMENT,                                                                                                                                                                                                       
`year` int(11) NOT NULL,                                                                                                                                                                                                                    
`country_id` int(11) NOT NULL,                                                                                                                                                                                                              
`created_at` datetime NOT NULL,                                                                                                                                                                                                             
`updated_at` datetime NOT NULL,                                                                                                                                                                                                             
PRIMARY KEY (`id`),                                                                                                                                                                                                                         
UNIQUE KEY `tournaments_year_unique` (`year`),                                                                                                                                                                                             
KEY `tournaments_country_id_foreign` (`country_id`),                                                                                                                                                                                      
CONSTRAINT `tournaments_country_id_foreign` FOREIGN KEY (`country_id`) REFERENCES `countries` (`id`) ON UPDATE CASCADE                                                                                                                  
) ENGINE=InnoDB AUTO_INCREMENT=40 DEFAULT CHARSET=latin1

Countries Model (countries.php)

class Country extends Eloquent {
    public static $timestamps = true;
    public static $table = 'countries';
}

Tournaments Model (tournaments.php)

class Tournament extends Eloquent {
    public static $timestamps = true;

    public function country()
    {
        return $this->has_one('Country');
    }
}

Upvotes: 42

Views: 8110

Answers (4)

sturrockad
sturrockad

Reputation: 4570

According to the Eloquent docs:

Note: All methods available on the query builder are also available when querying Eloquent models.

So with that in mind something like:

DB::table("tournament")->join("countries","tournaments.country_id","=","countries.id")->get();

Should be replicable in Eloquent. I personally use the query builder version just now which you may want to use but I will try and test with Eloquent when I get the chance and update this.

UPDATE:

Yep, using Eloquent's query builder methods you can have:

Tournament::join("countries","tournaments.country_id","=","countries.id")->get();

This will return a Tournament model that includes the fields of both tables.

HTH

Upvotes: 2

Karl
Karl

Reputation: 595

You have to make sure your relationship is declared in your Tournament model:

public function country() {
    return $this->has_one('Country');
}

Also, you will have to declare the opposite in your Country model:

public function tournament() {
    return $this->belongs_to('Tournament');
}

At this point, you can access the tournament object associated with the country object like so:

$tournaments = Tournament::with('country')->all();
foreach ($tournaments as $tournament) {
    echo $tournament->country;
}

Let me know if this display each corresponding country to the tournament.

Upvotes: 0

crynobone
crynobone

Reputation: 1814

Clearly with('Country') or with('country') doesn't do any different due to the fact that he managed to get following error:

Column not found: 1054 Unknown column 'tournament_id' in 'where clause'

SQL: SELECT * FROM `countries` WHERE `tournament_id` IN (?)

What wrong is how the relationship is defined: A tournament must have a country would be a tournament need to belong to a country, and not has one country. So to solve this change the relationship to

public function country()
{
    return $this->belongs_to('Country');
}

Upvotes: 10

James Healey
James Healey

Reputation: 464

Your 'with' clause asks for 'Country', but your code declares it as 'country'.

So, should:

$tournaments = Tournament::with('Country')->all();

Be:

$tournaments = Tournament::with('country')->all();

Because in your Tournaments Model, you've defined this as:

public function country()
{
    return $this->has_one('Country');
}

Does making this change solve it?

Upvotes: 1

Related Questions