Laravel在訪問關係屬性時忽略了熱切的加載關係

Question

我有兩個實體，NewCar和CapModel。我使用的關係是belongsTo，每個NewCar屬於一個CapModel。

相應的連接是：NewCar.model_code = CapModel.mod_code

我的控制器代碼使用預先加載：

public function rawData() 
{ 
    $cars = NewCar::with('capmodel')->take(20)->get(); 

    return View::make('new-cars.raw-data', compact('cars')); 
} 

我NewCar型號：

public function capModel() 
{ 
    return $this->belongsTo('CapModel', 'model_code', 'mod_code'); 
} 

我CapModel型號：

public function cars() 
{ 
    return $this->hasMany('NewCar', 'model_code', 'mod_code'); 
} 

我認爲，試圖訪問渴望加載的模型的屬性：

{{ $car->capModel->body_styles }} 

最後，運行的查詢。請注意，熱切的加載發生在頂部，但隨後的查詢也會運行。

select * from `listings_new_cars`265ms 
select * from `cap_model` where `cap_model`.`mod_code` in ('61163', '61162', '53880', '53869', '53848', '53847', '50253', '50250', '64738', '52477', '52476', '52475', '52474', '64736', '64735', '59178', '59177', '66648', '66639', '61321', '61287', '44962', '52707', '52703', '52716', '52712', '50006', '50000', '50687', '52736', '57436', '47162', '50499', '49830', '44985', '51566', '51565', '57165', '51941', '66160', '66154', '66144', '49569', '49554', '49615', '49681', '49670', '49742', '48973', '58273', '58268', '46090', '50536', '46091', '51585', '60772', '62079', '62078', '62059', '62058', '52797', '54484', '46663', '46662', '66719', '66708', '61433', '53136', '53129', '64355', '64352', '61129', '59771', '59706', '54969', '62587', '63176', '63172', '66137', '57096', '57095', '56799', '56798', '49822', '49821', '58451', '50979', '50978', '66424', '50977', '50976', '65022', '64213', '64206', '63262', '63253', '50981', '50980', '64926', '64912', '64871', '64857', '48072', '48052', '59090', '67120', '67112', '59200', '61878', '61877', '67071', '67085', '65972', '67853', '67778', '67337', '67336', '67358', '66759', '66758', '67896', '67939', '67940', '67899', '67105', '67098', '68435', '52578', '68609', '68603', '68937', '68897', '68896', '68866', '69418', '69420', '69416', '69847', '69838', '69810', '69757', '69692', '69691', '70133', '70213', '70195', '70210', '70171', '70177', '70294', '69672', '69642', '69661', '69631', '69837', '71435', '71422', '71413', '71404', '71376', '71364', '71718', '71609', '71598', '72209', '71867', '71872', '71842', '71841', '71843', '71875', '72776', '72781')26ms 
select * from `cap_model` where `cap_model`.`mod_code` = '61163' limit 1 17ms 
select * from `cap_model` where `cap_model`.`mod_code` = '61163' limit 1 18ms 
select * from `cap_model` where `cap_model`.`mod_code` = '61163' limit 1 
select * from `cap_model` where `cap_model`.`mod_code` = '61163' limit 1 18ms 
select * from `cap_model` where `cap_model`.`mod_code` = '61163' limit 1 19ms 
select * from `cap_model` where `cap_model`.`mod_code` = '61163' limit 1 17ms 
select * from `cap_model` where `cap_model`.`mod_code` = '61163' limit 1 17ms 
select * from `cap_model` where `cap_model`.`mod_code` = '61163' limit 1 17ms 
select * from `cap_model` where `cap_model`.`mod_code` = '61163' limit 1 17ms 
select * from `cap_model` where `cap_model`.`mod_code` = '61163' limit 1 19ms 
select * from `cap_model` where `cap_model`.`mod_code` = '61163' limit 1 19ms 
select * from `cap_model` where `cap_model`.`mod_code` = '61163' limit 1 17ms 
select * from `cap_model` where `cap_model`.`mod_code` = '61163' limit 1 18ms 
select * from `cap_model` where `cap_model`.`mod_code` = '61163' limit 1 

那麼，爲什麼Laravel不理我渴望加載和運行，而不是N + 1個查詢？代碼「起作用」，因爲它獲得了該屬性，但它運行了1700個查詢，每個車都有1個查詢。

Answer 1

將NewCar::with('capmodel')更改爲NewCar::with('capModel')，我遇到過這種類似的情況，可能會對您有所幫助。