SQLSTATE [42S22]：未找到列：1054未知列一对多（反）关系laravel

I have two models Tour.php and TourCategory.php:

Tour.php

protected $table = `tours`;

public function category() 
{
    return $this->belongsTo('App\TourCategory');
}

TourCategory.php

protected $table = 'tcategories';

public function tours()
{
    return $this->hasMany('App\Tour');
}

My db tables are as follows:

tours table

id|title|category_id|content|

tcatgegories table

id|name

And I have a view to show the all tours belonging to a category with the following code:

    @foreach ($category->tours as $tour)
     <tr>
        <th>{{ $tour->id}}</th>
        <td>{{ $tour->title}}</td>
        <td>
            <span class="label label-default">{{$category->name}}</span>
        </td>
     </tr>
    @endforeach

With this above code I'm getting error of:

SQLSTATE[42S22]: Column not found: 1054 Unknown column 'tours.tour_category_id' in
'where clause' (SQL: select * from `tours` where `tours`.`tour_category_id` = 1 and 
`tours`.`tour_category_id` is not null) (View: F:\multiauth_tutorial-masteresources\
views\admin\categories\show.blade.php

I have used same code for my previous projects also but didn't had any errors. Or am I missing something ?

Eloquent determines the default foreign key name by examining the name of the relationship method and suffixing the method name with _id. However, if the foreign key on the model is not *_id, you may pass a custom key name as the second argument to the belongsTo method

So, you need to specify a foreign key:

public function category() 
{
    return $this->belongsTo('App\TourCategory', 'category_id');
}

You may also override the foreign and local keys by passing additional arguments to the hasMany method.

public function tours()
{
    return $this->hasMany('App\Tour', 'category_id');
}

https://laravel.com/docs/5.4/eloquent-relationships#one-to-many

Or use tour_category_id instead of category_id in the tours table.

this column tour_category_id lis not found in your tours table, change your sql query to

select * from `tours` where `tours`.`category_id` = 1 and `tours`.`category_id` is not null

in Tour.php

 /**
 * @return \Illuminate\Database\Eloquent\Relations\HasMany
 */
public function tours()
{
    return $this->hasMany(Tour::class, 'category_id');
} 

in TourCategory.php

/**
     * @return \Illuminate\Database\Eloquent\Relations\BelongsTo
     */
    public function category()
    {
        return $this->belongsTo(TourCategory::class, 'category_id');
    }