您可以使用此包获取加载页面时正在执行的所有查询

https://github.com/barryvdh/laravel-debugbar

从Laravel 5.8.15开始，查询生成器现在有dd和dump方法

DB::table('data')->where('a', 1)->dump();

$data = User::toSql();
echo $data; //this will retrun select * from users. //here User is model

最简单的方法是故意犯错误。例如，我想查看以下关系的完整SQL查询：

public function jobs()
{
    return $this->belongsToMany(Job::class, 'eqtype_jobs')
        ->withPivot(['created_at','updated_at','id'])
        ->orderBy('pivot_created_at','desc');
}

我只是想创建一个找不到的列，这里我选择了created_at，并通过添加尾随s将其更改为created_ats：

public function jobs()
{
    return $this->belongsToMany(Job::class, 'eqtype_jobs')
        ->withPivot(['created_ats','updated_at','id'])
        ->orderBy('pivot_created_at','desc');
}

因此，调试器将返回以下错误：

（4/4）ErrorException SQLSTATE[42S22]：未找到列：1054未知“字段列表”中的列“eqtype_jobs.created_ats”（SQL:selectjobs.*，eqtype_jobs.set_id作为pivot_set_id，eqtype_jobs.job_id作为pivot_job_id，eqtype_jobs.created_ats作为pivot_created_ats，eqtype_jobs.updated_at作为pivot_updated_at，eqtype_jobs.id作为内部作业的pivot_id在jobs.id上加入eqtype_jobs.job_id，其中eqtype_jobs.set_id=56在desc limit 20时按pivot_created排序偏移量0）（视图：/home/ssad/www/factory/resources/views/set/show.blade.php）

上面的错误消息返回带有错误的完整SQL查询

SQL: select  jobs.*, eqtype_jobs.set_id as pivot_set_id,  eqtype_jobs.job_id as pivot_job_id, eqtype_jobs.created_ats as pivot_created_ats, eqtype_jobs.updated_at as  pivot_updated_at, eqtype_jobs.id as pivot_id from jobs inner join eqtype_jobs on jobs.id = eqtype_jobs.job_id where  eqtype_jobs.set_id = 56 order by pivot_created_at desc limit 20 offset 0

现在，只需从created_at中删除多余的s，并在任何SQL编辑器（如phpMyAdmin SQL编辑器）中测试该SQL！

###通知：该溶液已经用Laravel 5.4进行了测试。

如果您使用的不是Laravel，而是Elquent包，那么：

use \Illuminate\Database\Capsule\Manager as Capsule;
use \Illuminate\Events\Dispatcher;
use \Illuminate\Container\Container;

$capsule = new Capsule;

$capsule->addConnection([
    // connection details
]);
// Set the event dispatcher used by Eloquent models... (optional)
$capsule->setEventDispatcher(new Dispatcher(new Container));

// Make this Capsule instance available globally via static methods... (optional)
$capsule->setAsGlobal();

// Setup the Eloquent ORM...(optional unless you've used setEventDispatcher())
$capsule->bootEloquent();

// Listen for Query Events for Debug
$events = new Dispatcher;
$events->listen('illuminate.query', function($query, $bindings, $time, $name)
{
    // Format binding data for sql insertion
    foreach ($bindings as $i => $binding) {
        if ($binding instanceof \DateTime) {
            $bindings[$i] = $binding->format('\'Y-m-d H:i:s\'');
        } else if (is_string($binding)) {
            $bindings[$i] = "'$binding'";`enter code here`
        }
    }

    // Insert bindings into query
    $query = str_replace(array('%', '?'), array('%%', '%s'), $query);
    $query = vsprintf($query, $bindings);

    // Debug SQL queries
    echo 'SQL: [' . $query . ']';
});

$capsule->setEventDispatcher($events);

您可以收听“illumination.query”事件。在查询之前，添加以下事件侦听器：

Event::listen('illuminate.query', function($query, $params, $time, $conn) 
{ 
    dd(array($query, $params, $time, $conn));
});

DB::table('users')->get();

这将打印出如下内容：

array(4) {
  [0]=>
  string(21) "select * from "users""
  [1]=>
  array(0) {
  }
  [2]=>
  string(4) "0.94"
  [3]=>
  string(6) "sqlite"
}