我创建了一些简单的函数来从一些查询中获取SQL和绑定。

/**
 * getSql
 *
 * Usage:
 * getSql( DB::table("users") )
 * 
 * Get the current SQL and bindings
 * 
 * @param  mixed  $query  Relation / Eloquent Builder / Query Builder
 * @return array          Array with sql and bindings or else false
 */
function getSql($query)
{
    if( $query instanceof Illuminate\Database\Eloquent\Relations\Relation )
    {
        $query = $query->getBaseQuery();
    }

    if( $query instanceof Illuminate\Database\Eloquent\Builder )
    {
        $query = $query->getQuery();
    }

    if( $query instanceof Illuminate\Database\Query\Builder )
    {
        return [ 'query' => $query->toSql(), 'bindings' => $query->getBindings() ];
    }

    return false;
}

/**
 * logQuery
 *
 * Get the SQL from a query in a closure
 *
 * Usage:
 * logQueries(function() {
 *     return User::first()->applications;
 * });
 * 
 * @param  closure $callback              function to call some queries in
 * @return Illuminate\Support\Collection  Collection of queries
 */
function logQueries(closure $callback) 
{
    // check if query logging is enabled
    $logging = DB::logging();

    // Get number of queries
    $numberOfQueries = count(DB::getQueryLog());

    // if logging not enabled, temporarily enable it
    if( !$logging ) DB::enableQueryLog();

    $query = $callback();

    $lastQuery = getSql($query);

    // Get querylog
    $queries = new Illuminate\Support\Collection( DB::getQueryLog() );

    // calculate the number of queries done in callback
    $queryCount = $queries->count() - $numberOfQueries;

    // Get last queries
    $lastQueries = $queries->take(-$queryCount);

    // disable query logging
    if( !$logging ) DB::disableQueryLog();

    // if callback returns a builder object, return the sql and bindings of it
    if( $lastQuery )
    {
        $lastQueries->push($lastQuery);
    }

    return $lastQueries;
}

用法：

getSql( DB::table('users') );
// returns 
// [
//     "sql" => "select * from `users`",
//     "bindings" => [],
// ]

getSql( $project->rooms() );
// returns
// [
//     "sql" => "select * from `rooms` where `rooms`.`project_id` = ? and `rooms`.`project_id` is not null",
//     "bindings" => [ 7 ],
// ]

从laravel 5.2开始。您可以使用DB:：listen获取执行的查询。

DB::listen(function ($query) {
    // $query->sql
    // $query->bindings
    // $query->time
});

或者，如果要调试单个Builder实例，则可以使用toSql方法。

DB::table('posts')->toSql(); 

要将上次运行的查询输出到屏幕，可以使用以下命令：

\DB::enableQueryLog(); // Enable query log

// Your Eloquent query executed by using get()

dd(\DB::getQueryLog()); // Show results of log

我相信最近的查询将位于阵列的底部。

你会得到这样的东西：

array(1) {
  [0]=>
  array(3) {
    ["query"]=>
    string(21) "select * from "users""
    ["bindings"]=>
    array(0) {
    }
    ["time"]=>
    string(4) "0.92"
  }
}

（感谢约书亚在下面的评论。）

将此代码添加到AppServiceProvider并获取日志文件

         \DB::listen(function ($query) {
             \Log::info(
                 $query->sql,
                 $query->bindings,
                 $query->time
             );
         });

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。

为了记录所有执行的查询，可以使用DB:：enableQueryLog（）icw DB:：getQueryLog（（）。输出具有以下结构。

[
  [
    "query" => "select * from "users" where name = ?"
    "bindings" => ["John Doe"]
    "time" => 0.34
  ],
  ...
]

此外，我在这里结合了一些答案，以便获得完美的函数，用编译的绑定解析sql。见下文。我甚至创建了一个实现此功能的自定义生成器类，例如User:：where（'name'，'JohnDoe'）->parse（）；

function parse_sql(string $sql, array $bindings) : string
{
  $compiled_bindings  = array_map('compile_binding', $bindings);

  return preg_replace_array("/\?/", $compiled_bindings, $sql);
}

function compile_binding($binding)
{
  $grammar = new MySqlGrammar;

  if (is_bool($binding))
  {
    return (int)$binding; //This line depends on the database implementation
  }

  if(is_string($binding))
  {
    return "'$binding'";
  }

  if ($binding instanceof DateTimeInterface)
  {
    return $binding->format($grammar->getDateFormat());
  }

  return $binding;
}