mongodb-query

问题 I have collection database with 10 000 000 call records. I want to compare call usage of previous month to next month. Example of collection document { "_id" : ObjectId("54ed74d76c68d23af73e230a"), "msisdn" : "9818441000", "callType" : "ISD" "duration" : 10.109999656677246, "charges" : 200, "traffic" : "Voice", "Date" : ISODate("2014-01-05T19:51:01.928Z") } { "_id" : ObjectId("54ed74d76c68d23af73e230b"), "msisdn" : "9818843796", "callType" : "Local", "duration" : 1, "charges" : 150, "traffic"

问题 I have searched online but could not find any match my case. Here is the situation. I am using aggregate to combine one collection and one document which is from another collection together restaurants.aggregate([ { $match: { _id: { $in: idList } } }, { $lookup: { from: "tags", localField: "details.restaurantType", foreignField: "details.restaurantType._id", as: "types" } }, { $project: { restaurantName: "$details.restaurantName", restaurantType: "$details.restaurantType", type: { $filter: {

问题 Let's imagine I have the following collection of books (Edited out the ID field for compactness): { "author" : "Steve Jones", "title" : "Fun Stuff", "edition" : "2010" } { "author" : "Steve Jones", "title" : "Fun Stuff", "edition" : "2011" } { "author" : "Steve Jones", "title" : "Boring Stuff", "edition" : "2010" } { "author" : "Ben Johnson", "title" : "Other Stuff", "edition" : "2010" } What should I do I want to find only the latest edition of each book? In other words: I want to get a

问题 Let's imagine I have the following collection of books (Edited out the ID field for compactness): { "author" : "Steve Jones", "title" : "Fun Stuff", "edition" : "2010" } { "author" : "Steve Jones", "title" : "Fun Stuff", "edition" : "2011" } { "author" : "Steve Jones", "title" : "Boring Stuff", "edition" : "2010" } { "author" : "Ben Johnson", "title" : "Other Stuff", "edition" : "2010" } What should I do I want to find only the latest edition of each book? In other words: I want to get a

问题 I am looking for a value in a Mongo table where its parent key might not have a descriptive or known name. Here is an example of what one of our documents looks like. { "assetsId": { "0": "546cf2f8585ffa451bb68369" }, "slotTypes": { "0": { "usage": "json" }, "1": { "usage": "image" } } } I am looking to see if this contains "usage": "json" in slotTypes, but I can't guarantee that the parent key for this usage will be "0". I tried using the following query without any luck: db.documents.find(

问题 I'm trying to make this query to my collection Audios var querySlow = { "palabra": { $regex: "^" + keywords, "$options": "i" }, $or: [{ "_p_pais": { $in: interested_accents } }, { "languageCodeTatoeba": { $in: interested_accents_tatoeba } }] }; // takes 20 seconds This is actually really really slow but if I remove any of the $or , it is very very fast , for example: var queryFast1 = { "palabra": { $regex: "^" + keywords, "$options": "i" }, $or: [{ "_p_pais": { $in: interested_accents } }] };

问题 I'm trying to make this query to my collection Audios var querySlow = { "palabra": { $regex: "^" + keywords, "$options": "i" }, $or: [{ "_p_pais": { $in: interested_accents } }, { "languageCodeTatoeba": { $in: interested_accents_tatoeba } }] }; // takes 20 seconds This is actually really really slow but if I remove any of the $or , it is very very fast , for example: var queryFast1 = { "palabra": { $regex: "^" + keywords, "$options": "i" }, $or: [{ "_p_pais": { $in: interested_accents } }] };

问题 I'm trying to make this query to my collection Audios var querySlow = { "palabra": { $regex: "^" + keywords, "$options": "i" }, $or: [{ "_p_pais": { $in: interested_accents } }, { "languageCodeTatoeba": { $in: interested_accents_tatoeba } }] }; // takes 20 seconds This is actually really really slow but if I remove any of the $or , it is very very fast , for example: var queryFast1 = { "palabra": { $regex: "^" + keywords, "$options": "i" }, $or: [{ "_p_pais": { $in: interested_accents } }] };

问题 I have been trying to validate my data using the validators provided by MongoDB but I have run into a problem. Here is a simple user document which I am inserting. { "name" : "foo", "surname" : "bar", "books" : [ { "name" : "ABC", "no" : 19 }, { "name" : "DEF", "no" : 64 }, { "name" : "GHI", "no" : 245 } ] } Now, this is the validator which has been applied for the user collection. But this is now working for the books array which I am inserting along with the document. I want to check the

问题 I am running the same aggregation pipeline with a Spark Application and on the Mongos console. On the console, the data is fetched within the blink of an eye, and only a second use of "it" is needed to retrieve all expected data. The Spark Application however takes almost two minutes according to the Spark WebUI. As you can see, 242 tasks are being launched to fetch the result. I am not sure why such an high amount of tasks is launched while there are only 40 documents being returned by the