(MongoDB Java) $push 到数组 [英] (MongoDB Java) $push into array

问题描述

我使用的是 mongo 2.2.3 和 java 驱动程序.我的困境，我必须将一个字段和值 $push 到一个数组中，但我似乎无法弄清楚如何做到这一点.我的数据示例:

I'm using mongo 2.2.3 and the java driver. My dilemma, I have to $push a field and value into an array, but I cant seem to figure out how to do this. A sample of my data:

"_id" : 1,
"scores" : [
    {
        "type" : "homework",
        "score" : 78.97979
    },
    {
        "type" : "homework",
        "score" : 6.99
    },
    {
        "type" : "quiz",
        "score" : 99
    }
]

我可以在 shell 中 $push:

I can $push in the shell:

db.collection.update({_id:1},{$push:{scores:{type:"quiz", score:99}}})

但是当我把它翻译成 Java 时，我把自己弄糊涂了，把我的键盘扔到墙上.

but it's when I translate this into java I confuse my self and chuck my keyboard at a wall.

到目前为止我的java代码(不完整和错误):

my java code (incomplete and wrong) so far:

DBObject find = new BasicDBObject("_id", 1);
DBObject push = new BasicDBObject("$push", new BasicDBObject(
                        "scores", new BasicDBObject()));

推荐答案

DBObject listItem = new BasicDBObject("scores", new BasicDBObject("type","quiz").append("score",99));
DBObject updateQuery = new BasicDBObject("$push", listItem);
myCol.update(findQuery, updateQuery);

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