laravel 5.5 打印sql

用DB自带的getQueryLog方法直接打印：

DB::connection()->enableQueryLog();  // 开启QueryLog
\App\User::find(1);
dump(DB::getQueryLog());

若要打印出完整的sql语句，可将以下代码复制到AppServiceProvider中的boot方法中：

\DB::listen(
    function ($sql) {
        foreach ($sql->bindings as $i => $binding) {
            if ($binding instanceof \DateTime) {
                $sql->bindings[$i] = $binding->format('\'Y-m-d H:i:s\'');
            } else {
                if (is_string($binding)) {
                    $sql->bindings[$i] = "'$binding'";
                }
            }
        }

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

        $query = vsprintf($query, $sql->bindings);

        // Save the query to file
        $logFile = fopen(
            storage_path('logs' . DIRECTORY_SEPARATOR . date('Y-m-d') . '_query.log'),
            'a+'
        );
        fwrite($logFile, date('Y-m-d H:i:s') . ': ' . $query . PHP_EOL);
        fclose($logFile);
    }
);

日志在storage/log/xxx_query.log