Thinkphp5 预加载 延时加载记录

在做购物表格时用到主表：goods 附表   goodscate

这个时候需要把模型关联查询出来可以用到预加载和延时加载

原查询为：

$content = $model->where($where)->order('create_time desc')->page($page)->limit($limit)->select();

普通关联为：   缺点 SQL套嵌繁琐  数据多情况下 加载给数据库带来压力   不推荐 

$content = $model->where($where)->order('create_time desc')->page($page)->limit($limit)->select();
     foreach ($content as $key => $value) {
            $value->goodscate;
     }

预加载关联为：

$content = $model::with('googscate')->where($where)->order('create_time desc')->page($page)->limit($limit)->select();
     foreach ($content as $key => $value) {
            $value->goodscate;
     }

延迟加载关联为：

$content = $model->where($where)->order('create_time desc')->page($page)->limit($limit)->select();
    $content=load_relation($content,'goodscate');//延迟预载入关联
    foreach ($content as $key => $value) {
            $value->goodscate;
     }