我只是在。env文件中做了一个更改

我有如下一行代码。

DB_CONNECTION=mysql
DB_HOST=localhost
DB_PORT=3306
DB_DATABASE=database_name
DB_USERNAME=root
DB_PASSWORD=

修改主机名localhost为127.0.0.1

DB_CONNECTION=mysql
DB_HOST=127.0.0.1
DB_PORT=3306
DB_DATABASE=database_name
DB_USERNAME=root
DB_PASSWORD=

这是在我的情况下工作，因为它不能找到任何主机名，如localhost

并在更改主机名后编写以下命令

php artisan config:clear
php artisan migrate:install
php artisan migrate

对于任何试图创建一个新的db连接而不是在laravel上，而是在这里寻找从终端运行PDO的答案的人。这对你有帮助。你可以重构它，使其最适合你。

<?php

class db
{
   private $DBHOST = 'localhost'; // you don't need 127.0.0.1
   private $DRIVER = 'mysql';
   private $PORT   = '8888'; // database port. 8888 is mine
   private $DB     = 'example-db';
   private $PASS   = 'example-pass';
   private $USER   = 'root';
   private $SOCKS  = ''; // can fill this or leave blank.


   // - connect (dummy connection)
   private function con()
   {
       if ($this->SOCKS == '')
       {
           // run shell command to get 
           $socks = shell_exec('netstat -ln | grep mysql');
           $socks = trim(substr($socks, strpos($socks, '/')));

           $this->SOCKS = strlen($socks) > 0 ? ';unix_socket='.$socks : '';
       }
       else
       {
          $this->SOCKS = ';unix_socket='.$this->SOCKS;
       }

       $dsn = $this->DRIVER.':host='.$this->DBHOST.';dbname='.$this->DB;

       // add socks
       $dsn .= $this->SOCKS;

       // add port
       $dsn .= (strlen($this->PORT) > 0) ? ';port='.$this->PORT : '';

       // extablish connection
       $con = new PDO($dsn, $user, $pass);

       // return PDO instance.
       return $con;
   }
   // - ends here

   // now you can call $this->con() within class to use connection 
   // would run fine on any terminal

} 

希望能有所帮助!

如果你使用Laravel Homestead， 这里是设置

(包括流浪者-虚拟机)

.bash-profile

alias vm="ssh vagrant@127.0.0.1 -p 2222"

database.php

    'mysql' => [
        'driver'    => 'mysql',
        'host'      => env('DB_HOST', '127.0.0.1'),
        'database'  => env('DB_DATABASE', 'homestead'),
        'username'  => env('DB_USERNAME', 'homestead'),
        'password'  => env('DB_PASSWORD', 'secret'),
        'charset'   => 'utf8',
        'collation' => 'utf8_unicode_ci',
        'prefix'    => '',
        'strict'    => false,
    ],

终端

vm

vagrant@homestead:~/Code/projectFolder  php artisan migrate:install

当使用VirtualMachine时，确保你ssh到那台机器，导航到你的App文件夹，并从那里调用php artisan migrate命令。

要添加到@alexventuraio的解决方案中，如果你在Laravel 5.8上遇到了这个问题，你可能想要替换数据库配置文件中'unix_socket'的值，如下:

 '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', ''),
        // 'unix_socket' =>'/var/run/mysqld/mysqld.sock',
        'unix_socket' => env('DB_SOCKET', ''), // replace with this line, so you can always add the mysqld.sock from the dotenv file
        'charset' => 'utf8mb4',
        'collation' => 'utf8mb4_unicode_ci',
        'prefix' => '',
        'prefix_indexes' => true,
        'strict' => false,
        'engine' => null,
        'options' => extension_loaded('pdo_mysql') ? array_filter([
            PDO::MYSQL_ATTR_SSL_CA => env('MYSQL_ATTR_SSL_CA'),
        ]) : [],
    ],

由于不同的原因，我遇到了[PDOException] SQLSTATE[HY000] [2002] No这样的文件或目录错误。我刚刚在Ubuntu 12.04上用Apache 2.4.7、PHP v5.5.10和MySQL 5.6.16构建了一个全新的LAMP堆栈。我把我的网站搬了回来，重新启动。但是，我无法加载我的Laravel 4.2。基于x的站点，因为上面的[PDOException]。所以，我检查了php -i | grep pdo，并注意到这一行:

pdo_mysql.default_socket => /tmp/mysql.sock => /tmp/mysql.sock

但是，在我的/etc/my.cnf中，sock文件实际上在/var/run/mysqld/mysqld.sock中。

因此，我打开php.ini并设置pdo_mysql.default_socket的值:

pdo_mysql.default_socket=/var/run/mysqld/mysqld.sock

然后，我重新启动apache并检查php -i | grep pdo:

pdo_mysql.default_socket => /var/run/mysqld/mysqld.sock => /var/run/mysqld/mysqld.sock

这为我解决了问题。