php 三级菜单数据的读取
这里的数据要怎么读取?
第二级: 表明:category category_id category_name(二级名次)
第三级: 表明:subcategory subcategory_id subcategory_name(三级名称) subcategory_category(与category表id管理)
现在我的做法
//查出第二级的数据
$result = select category_id,category_name from category;数据返回的结果
//查出第三级的数据
foreach($result as $k=>$v){
$result2[]=select subcategory_name from subcategory where subcategory_category=$v['category_id']返回你的结果;
}
这样好吗?数据库被访问了多次
回复讨论(解决方案)
为什么不可以？
如果你只想读取一次 subcategory，那么可以读出 subcategory 的全部数据
逐条填写到 $result 中去
多层级用递归就是这样的
这样数据库操作频繁,sql执行了多次
您是耽心数据库会累吗？
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