分层评论，亲子关系

Question

我正在尝试为我的网站制作类似reddit的评论。我有这个数据库结构（MySql）：

parent_id | comment_id | comment

这是来自数据库的示例数据：

var data = [
    {comment_id: "1a", parent_id: "", comment: "11111"},
    {comment_id: "2a", parent_id: "1a", comment: "22222"},
    {comment_id: "3a", parent_id: "1a", comment: "33333"},
    {comment_id: "4a", parent_id: "3a", comment: "44444"},
    {comment_id: "5a", parent_id: "", comment: "55555"},
    {comment_id: "6a", parent_id: "5a", comment: "6666"},
]
// if parent_id == "", it's parent.

我需要与它的孩子建立该列表关系。我做了，但我不能实现递归，所以父母只是范围first childs。

我的实施：

function parse(arr) {

    var mothers = []

    //find mothers

    for (var i = 0; i < arr.length; i++) {

        //if parent_id == "" => it's mother.

        if(arr[i].parent_id == "") {
            arr[i].childs = [] // make it's childs
            mothers.push(arr[i])
            arr = _.without(arr, arr[i])
        }
    }

    var childs = arr

    for (var i = 0; i < childs.length; i++) {
        var possibleChild = childs[i]

        var parent_id = possibleChild.parent_id

        for (var z = 0; z < mothers.length; z++) {
            var mother = mothers[z]

            if(mother.comment_id == parent_id){ // match it with mother
                mother.childs.push(possibleChild)
            }
        }
    }

    return mothers

}

有人可以帮忙吗？感谢。