php - 绑定参数到 Db::raw laravel 查询

Question

我有以下原始查询：

$results = Db::select( Db::raw("SELECT HOUR(created_at) as hour, COUNT(*) as count
                       FROM `visited`
                       WHERE created_at >= DATE_SUB(NOW(),INTERVAL 16 DAY)
                       GROUP BY HOUR(created_at)") );

我需要参数化天间隔，所以我尝试了这个：

$days = 16;
$results = Db::select( Db::raw("SELECT HOUR(created_at) as hour, COUNT(*) as count
                       FROM `visited`
                       WHERE created_at >= DATE_SUB(NOW(),INTERVAL :days DAY)
                       GROUP BY HOUR(created_at)", ["days" => $days]) );

但我收到以下错误：

“SQLSTATE [HY000]：一般错误：2031

显然绑定不起作用。我究竟做错了什么？

Answer 1

尝试这个：

$results = DB::select('SELECT HOUR(created_at) as hour, COUNT(*) as count FROM visited WHERE created_at >= DATE_SUB(NOW(),INTERVAL ? DAY) GROUP BY HOUR(created_at)', [16]);

你甚至可以使用命名绑定：

$results = DB::select('SELECT HOUR(created_at) as hour, COUNT(*) as count FROM visited WHERE created_at >= DATE_SUB(NOW(),INTERVAL :days DAY) GROUP BY HOUR(created_at)', ['days' => 16]);

不需要使用DB::raw()，只需DB::select()用于简单的原始选择查询：https ://laravel.com/docs/master/database#running-queries