Laravel Eloquentの超基本的な使い方

モデルの取得

主キーで取得

SELECT * FROM users WHERE id = 1 LIMIT 1;

App\User::find(1);

全件取得

SELECT * FROM posts WHERE writer_id = 1;

App\Post::where('writer_id', 1)->get();

1件だけ取得

whereの引数を配列にすれば、And検索できる

SELECT * FROM favorites WHERE user_id = 1 AND post_id = 1 LIMIT 1;

App\Favorite::where([
    'user_id' => 1,
    'post_id' => 1,
])->first();

Or検索

And検索は ->where()->where() のようにメソッドチェーンでも書ける
また、メソッドチェーンは Or検索も表せる

SELECT * FROM posts WHERE title LIKE '%Lorem' OR title LIKE '%ipsum%';

App\Post::where('title', 'LIKE', '%Lorem')
->orWhere('title', 'LIKE', '%ipsum%')
->get();

複雑な検索

コールバックを使用すれば複雑な条件も表せる

SELECT * FROM posts
 WHERE (title LIKE '%Lorem' OR title LIKE '%ipsum%')
  AND (created_at IS NULL OR updated_at IS NULL);

App\Post::where(function ($query) {
    return $query
    ->where('title', 'LIKE', '%Lorem')
    ->orWhere('title', 'LIKE', '%ipsum%');
})
->where(function ($query) {
    return $query
    ->whereNull('created_at')
    ->orWhereNull('updated_at');
})->get();

モデルの作成

INSERT INTO favorites (user_id, post_id) VALUES (1, 2);

App\Favorite::create([
    'user_id' => 1,
    'post_id' => 2,
]);

モデルの更新

UPDATE posts SET updated_at = NOW();

App\Post::query()->update([
    'updated_at' => \Carbon\Carbon::now(),
]);

モデルの(物理)削除

DELETE FROM favorites WHERE user_id = 1 AND post_id = 1;

App\Favorite::where([
    'user_id' => 1,
    'post_id' => 1,
])->delete();

参考ページ
https://readouble.com/laravel/6.x/ja/eloquent.html
https://stackoverflow.com/questions/19325312/how-to-create-multiple-where-clause-query-using-laravel-eloquent
https://stackoverflow.com/questions/15622710/how-to-set-every-row-to-the-same-value-with-laravels-eloquent-fluent