php - 如何在 Laravel 中使用多个数据库

Question

我想在我的系统中合并多个数据库。大多数情况下，数据库是 MySQL；但将来可能会有所不同，即管理员可以生成这样的报告，它是使用异构数据库系统的来源。

所以我的问题是 Laravel 是否提供任何 Facade 来处理这种情况？或者任何其他框架有更适合问题的能力是什么？

Answer 1

测试版本(更新)

<头>

版本	已测试(是/否)
4.2	没有
5.x	是 (5.5)
6.x	没有
7.x	没有
8.x	是的 (8.4)
9.x	是的 (9.2)

---

定义连接

Using .env >= 5.0 (or higher)

在 .env

DB_CONNECTION=mysql
DB_HOST=127.0.0.1
DB_PORT=3306
DB_DATABASE=database1
DB_USERNAME=root
DB_PASSWORD=secret

DB_CONNECTION_SECOND=mysql
DB_HOST_SECOND=127.0.0.1
DB_PORT_SECOND=3306
DB_DATABASE_SECOND=database2
DB_USERNAME_SECOND=root
DB_PASSWORD_SECOND=secret

在 config/database.php

'mysql' => [
    'driver'    => env('DB_CONNECTION'),
    'host'      => env('DB_HOST'),
    'port'      => env('DB_PORT'),
    'database'  => env('DB_DATABASE'),
    'username'  => env('DB_USERNAME'),
    'password'  => env('DB_PASSWORD'),
],

'mysql2' => [
    'driver'    => env('DB_CONNECTION_SECOND'),
    'host'      => env('DB_HOST_SECOND'),
    'port'      => env('DB_PORT_SECOND'),
    'database'  => env('DB_DATABASE_SECOND'),
    'username'  => env('DB_USERNAME_SECOND'),
    'password'  => env('DB_PASSWORD_SECOND'),
],

Note: In mysql2 if DB_username and DB_password is same, then you can use env('DB_USERNAME') which is metioned in .env first few lines.

Without .env <= 4.0 (or lower)

app/config/database.php

return array(

    'default' => 'mysql',

    'connections' => array(

        # Primary/Default database connection
        'mysql' => array(
            'driver'    => 'mysql',
            'host'      => '127.0.0.1',
            'database'  => 'database1',
            'username'  => 'root',
            'password'  => 'secret'
            'charset'   => 'utf8',
            'collation' => 'utf8_unicode_ci',
            'prefix'    => '',
        ),

        # Secondary database connection
        'mysql2' => array(
            'driver'    => 'mysql',
            'host'      => '127.0.0.1',
            'database'  => 'database2',
            'username'  => 'root',
            'password'  => 'secret'
            'charset'   => 'utf8',
            'collation' => 'utf8_unicode_ci',
            'prefix'    => '',
        ),
    ),
);

---

架构/迁移

运行 connection()方法来指定要使用的连接。

Schema::connection('mysql2')->create('some_table', function($table)
{
    $table->increments('id'):
});

或者，在顶部，定义一个连接。

protected $connection = 'mysql2';

---

查询生成器

$users = DB::connection('mysql2')->select(...);

---

模型(在 Laravel >= 5.0(或更高版本)中)

设置$connection模型中的变量

class ModelName extends Model { // extend changed

    protected $connection = 'mysql2';

}

Eloquent(在 Laravel <= 4.0(或更低版本)中)

设置$connection模型中的变量

class SomeModel extends Eloquent {

    protected $connection = 'mysql2';

}

---

您也可以在运行时通过 setConnection 定义连接。方法或 on静态方法:

class SomeController extends BaseController {

    public function someMethod()
    {
        $someModel = new SomeModel;

        $someModel->setConnection('mysql2'); // non-static method

        $something = $someModel->find(1);

        $something = SomeModel::on('mysql2')->find(1); // static method

        return $something;
    }

}

Note: Be careful about attempting to build relationships with tables across databases! It is possible to do, but it can come with some caveats depending on your database and settings.

---

From Laravel Docs

使用多个数据库连接

当使用多个连接时，您可以访问每个 connection 通过 DB 上的连接方法 门面。 name 传递给 connection 方法应对应于您的 config/database.php 中列出的连接之一 配置文件:

$users = DB::connection('foo')->select(...);

您也可以使用 getPdo 访问原始的底层 PDO 实例。连接实例上的方法:

$pdo = DB::connection()->getPdo();

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有用的链接

1. Laravel 5 multiple database connections FROM laracasts.com
2. Connect multiple databases in Laravel FROM tutsnare.com
3. Multiple DB Connections in Laravel FROM fideloper.com