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 ],
// ]

有一种获取查询字符串的方法。

到SQL（）

在我们的情况下，

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

回来

select * from users

是返回SQL查询字符串的确切解决方案。。希望这有帮助。。。

下面是一个完美的例子：

https://laravel.com/docs/5.8/database#listening-用于查询事件

打开app\Providers\AppServiceProvider.php并将以下内容添加到Boot（）函数中：

DB::listen(function ($query) {
    var_dump([
        $query->sql,
        $query->bindings,
        $query->time
    ]);
});

因此，您不需要在每个函数中放置DB:：enableQuerylog（）和DB:：getQuerylog（（）。

以下是我使用的解决方案：

DB::listen(function ($sql, $bindings, $time) {
    $bound = preg_replace_callback("/\?/", function($matches) use ($bindings) {
        static $localBindings;
        if (!isset($localBindings)) {
            $localBindings = $bindings;
        }
        $val = array_shift($localBindings);

        switch (gettype($val)) {
            case "boolean":
                $val = ($val === TRUE) ? 1 : 0;  // mysql doesn't support BOOL data types, ints are widely used
                // $val = ($val === TRUE) ? "'t'" : "'f'";   // todo: use this line instead of the above for postgres and others
                break;

            case "NULL":
                $val = "NULL";
                break;

            case "string":
            case "object":
                $val = "'". addslashes($val). "'";   // correct escaping would depend on the RDBMS
                break;
        }
        return $val;
    }, $sql);
    array_map(function($x) { 
        (new \Illuminate\Support\Debug\Dumper)->dump($x); 
    }, [$sql, $bindings, $bound]);
});

请阅读代码中的注释。我知道，它并不完美，但对于我的日常调试来说，它还可以。它试图以或多或少的可靠性构建绑定查询。但是，不要完全信任它，数据库引擎以不同的方式对值进行转义，而这个短函数并没有实现这些值。所以，仔细观察结果。

我的方法是基于日志视图，只需修改app/Providers/AppServiceProvider.php文件：

将此代码添加到app/Provider/AppServiceProvider.php中

/**
 * Bootstrap any application services.
 *
 * @return void
 */
public function boot()
{
    //
    DB::listen(function ($query) {
        $querySql = str_replace(['?'], ['\'%s\''], $query->sql);
        $queryRawSql = vsprintf($querySql, $query->bindings);
        Log::debug('[SQL EXEC]', [
                "raw sql"  => $queryRawSql,
                "time" => $query->time,
            ]
        );
    });
}

我的sql句柄代码：

$users = DB::table('users')
    ->select(DB::raw('count(*) as user_count, username '))
    ->where('uid', '>=', 10)
    ->limit(100)
    ->groupBy('username')
    ->get()
;
dd($users);

参见日志存储/logs/laravel-2019-10-27.log：

[2019-10-27 17:39:17] local.DEBUG: [SQL EXEC] {"raw sql":"select count(*) as user_count, username  from `users` where `uid` >= '10' group by `username` limit 100","time":304.21} 

我通过监听查询日志并附加到日志数组来实现：

//create query
$query=DB::table(...)...->where(...)...->orderBy(...)...
$log=[];//array of log lines
...
//invoked on query execution if query log is enabled
DB::listen(function ($query)use(&$log){
    $log[]=$query;//enqueue query data to logs
});
//enable query log
DB::enableQueryLog();
$res=$query->get();//execute