MongoDB Query Inline Document

The documentation is as follows:

/* 0 */{  "_id": ObjectId ("55d09915331c571b60035d95"),  "title": "Hello World",  "comment": [{      "author" : "Joe",      "score": 3    }, {      "author": "Tom",      "score": 5    }, {      "author": "Jean",      "score": 9    }]} /* 1 */{  "_id": ObjectId ("55d0996a331c571b60035d96"),  "title": "Zhangsan",  "comment": [{      " Author ":" Joe ","      Score ": 7    }, {      " author ":" Suam ",      " score ": 2    }, {      " author ":" Jean ", 
    "Score": 3    }]}/* 2 */{  "_id": ObjectId ("55d099b1331c571b60035d97"),  "title": "Lisi",  "comment ": [{      " author ":" Wangwu ",      " Score ": 4    }, {      " author ":" Suam ",      " score ": 8    }, {      " Autho R ":" Tom ",      " score ": 6    }]}

Ask how to query author for Joe, and score for more than 5 comments.

The correct answer is

Db.test.find ({"comment": {"$elemMatch": {"author": "Joe", "score": {"$gte": 5}}})

If it is directly

Db.test.find ({"comment": {"author": "Joe", "score": {"$gte": 5}})

To query, the matching of the embedded document must match the entire document exactly.

If you use

Db.test.find ({"Comment.author": "Joe", "Comment.score": {"$GT": 5}})

Comments that meet auhor conditions and score conditions may not be the same, meaning that the following two documents will be queried

/* 0 */{  "_id": ObjectId ("55d09915331c571b60035d95"),  "title": "Hello World",  "comment": [{      "author" : "Joe",      "score": 3    }, {      "author": "Tom",      "score": 5    }, {      "author": "Jean",      "score": 9
   }]}/* 1 */{  "_id": ObjectId ("55d0996a331c571b60035d96"),  "title": "Zhangsan",  "comment": [{      "Author": "Joe",      "score": 7    }, {      "author": "Suam",      "score": 2    }, {      "author": "Jean", 
    "Score": 3    }]}

Copyright NOTICE: This article for Bo Master original article, without Bo Master permission not reproduced.

MongoDB Query Inline Document