mongodb-query

问题 I'm getting distinct values of field from mongodb. When i run the following query in the commandline, it works good. db.celldata.distinct("tenentId") I'm using Mongo java 3.0 driver, to retrieve the distinct values using the following query MongoCursor<String> iterator = coll.distinct("tenantId", String.class).iterator(); When i run the query i get the following exception org.bson.BsonInvalidOperationException: readString can only be called when CurrentBSONType is STRING, not when

问题 In mongodb, after a few $match and $project, I get the following 2 documents. I'm trying to figure out how to group/count together the list of states for each team in each group of each event. In short, I need to know how many teams are in each state (0, 1 or 2). I start out with the following documents. { "_id" : "event1", "groups" : [ { "_id" : "group1", "wlActive" : true, "teams" : [ {"state" : NumberInt(2)}, {"state" : NumberInt(2)}, {"state" : NumberInt(1)}, {"state" : NumberInt(1)}, {

问题 I would like to be able to dynamically build a Mongo query using Node with multiple OR's. The point of this query is to do an AND search in the database with multiple search terms. For example, suppose someone wanted to search for records containing the words "dog" and "cereal." The query would only return records that have "dog" and "cereal" somewhere in the record (i.e. the search terms can appear in different columns). I know that the query should end up looking like this: query = { $and:

问题 How can I query this nested json structure in order to find documents that contain "A"? "categories":[{"id":12,"values":[["A","B","C"]]},{"id":17,"values":[["D","E","F"]]}] So far, I only managed to get to the id value with db.coll.find( {categories: { $elemMatch: { id: 12 }}} ) 回答1: You need to nest the $elemMatch operators to match the nested levels of your arrays to match the element: db.coll.find({ "categories": { "$elemMatch": { "values": { "$elemMatch": { "$elemMatch": { "$in": ["A"] }

问题 Colleges { "_id" : ObjectId("5cd42b5c65b41027845938ae"), "clgID" : "100", "name" : "Vivekananda" }, { "_id" : ObjectId("5cd42b5c65b41027845938ad"), "clgID" : "200", "name" : "National" } Point : 1 => Take all clgID From Colleges collection. Subjects: { "_id" : ObjectId("5cd42c2465b41027845938b0"), "name" : "Hindi", "members" : { "student" : [ "123" ] }, "college" : { "collegeID" : "100" } }, { "_id" : ObjectId("5cd42c2465b41027845938af"), "name" : "English", "members" : { "student" : [ "456",

问题 I've collections of documents as like as below: { "_id" : ObjectId("55d4410544c96d6f6578f893"), "executionProject" : "Project1", "suiteList" : [ { "suiteStatus" : "PASS" } ], "runEndTime" : ISODate("2015-08-19T08:40:47.049Z"), "runStartTime" : ISODate("2015-08-19T08:40:37.621Z"), "runStatus" : "PASS", "__v" : 1 } { "_id" : ObjectId("55d44eb4c0422e7b8bffe76b"), "executionProject" : "Project1", "suiteList" : [ { "suiteStatus" : "PASS" } ], "runEndTime" : ISODate("2015-08-19T09:39:13.528Z"),

问题 I have the following mongodb structure { "_id": ObjectId("507c80a143188f9610000003"), "date": ISODate("2012-10-15T21: 31: 13.0Z"), "uid": NumberInt(35920), "comp": NumberInt(770), "fields": { "rating": { "parent": "rating", "weight": NumberInt(2), "rel_weight": 0.11, }, "capacity": { "parent": "capacity", "weight": NumberInt(4), "rel_weight": 0.89, }, } } The "fields" attribute has 2 fields "rating" and "capacity" in it. But, each entry might have a different set of fields. eg. dimension,

问题 I'm trying to make a query between two collections in mongodb using node js. I have these two collection in the db: Trip { "_id":ObjectId("55a922531e35772c1b17d4a0"), "name":"trip_name", "waypoints":[ "4c828999d8086dcb03877752", "4dd2ae657d8b4c6585f1a6fd", "4c59c3e4f346c928a8634dca" ], "line_points":[ [ 42.850937, 13.569256 ], [ 42.85109, 13.569377 ], [ 42.851131, 13.569225 ] ], "time":"00:10:23", "distance":6.622, "hashKey":"object:8207" }; Poi { "_id":"4c828999d8086dcb03877752", "type":

问题 I would like to get for each user in my collection the comment of the record with the highest value. //myCol [ {'user' : 1, 'value':20, "comment": "cloudy", "date":"2018-12-01"}, {'user' : 2, 'value':5, "comment": "sun","date":"2018-12-01"}, {'user' : 3, 'value':13, "comment": "rain","date":"2018-13-01"}, {'user' : 4, 'value':13, "comment": "cloudy","date":"2018-13-01"}, {'user' : 2, 'value':20, "comment": "rain","date":"2018-01-20"}, {'user' : 1, 'value':2, "comment": "cloudy","date":"2018

问题 I needed to find all the records in mongo db within two date ranges using Mongo Driver[3.4.0] for Java. Example: I have books Collection. { "_id" : ObjectId("5acb40d27d63b61cb002bafe"), "title" : "WingsOfFire", "pub-date" : ISODate("2013-10-02T00:00:00.000Z"), "rel-date" : ISODate("2013-11-02T00:00:00.000Z") } Like above I have 100s of documents. I need to find all records wherein pub-date > rel-date. I am using Mongo DB version 3.2.6 I tried to use $expr operator but it seems to work with