Laravel如何配置和使用多个数据库连接

'mysql' => [
    'driver' => 'mysql',
    'host' => env('DB_HOST', '127.0.0.1'),
    'port' => env('DB_PORT', '3306'),
    'database' => env('DB_DATABASE', 'forge'),
    'username' => env('DB_USERNAME', 'forge'),
    'password' => env('DB_PASSWORD', ''),
    // 其他配置...
],

'mysql_secondary' => [
    'driver' => 'mysql',
    'host' => env('DB_SECONDARY_HOST', '192.168.1.100'),
    'port' => env('DB_SECONDARY_PORT', '3306'),
    'database' => env('DB_SECONDARY_DATABASE', 'secondary_db'),
    'username' => env('DB_SECONDARY_USERNAME', 'user'),
    'password' => env('DB_SECONDARY_PASSWORD', ''),
    'charset' => 'utf8mb4',
    'collation' => 'utf8mb4_unicode_ci',
    'prefix' => '',
    'strict' => true,
    'engine' => null,
],

DB_SECONDARY_HOST=192.168.1.100
DB_SECONDARY_PORT=3306
DB_SECONDARY_DATABASE=secondary_db
DB_SECONDARY_USERNAME=user
DB_SECONDARY_PASSWORD=secret

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class SecondaryUser extends Model
{
    protected $connection = 'mysql_secondary';
    protected $table = 'users';
}

// 使用默认连接
$users = DB::table('users')->get();

// 使用 mysql_secondary 连接
$secondaryUsers = DB::connection('mysql_secondary')->table('users')->get();

DB::connection('mysql_secondary')->transaction(function () {
    DB::connection('mysql_secondary')->table('logs')->insert([
        'action' => 'user_login',
        'created_at' => now()
    ]);
});

$userModel = new SecondaryUser();
$userModel->setConnection('mysql_secondary');
$users = $userModel->get();
// 记得恢复，避免影响后续调用
$userModel->setConnection(null);

public function getUsersFrom($connectionName)
{
    return DB::connection($connectionName)->table('users')->get();
}