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Format exception - RavenDB LINQ query

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问题 I am getting a input string format error in the following bit of code... While debugging code, this runs as a single line of code and so I am not able to dig deep into what might be causing the format exception.. can any one please point to me what I am doing wrong.. thank you. Exception: FormatException was unhandled by user code: "Input string was not in correct format" Code: store.DatabaseCommands.UpdateByIndex("Movies/NewIndexName", new IndexQuery { Query = string.Format("Status:Released

MongoDb的相关资料

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MongoDb的相关资料 MongoLive：在Chrome里进行MongoDB实时监控 http://blog.nosqlfan.com/html/1964.html MongoDB的局限性与不足 http://blog.nosqlfan.com/html/3166.html Admin Zone http://www.mongodb.org/display/DOCS/Admin+Zone MongoDB Administration http://blog.nosqlfan.com/html/1747.html 工具 MongoVUE 这是老外开发的一个工具。 MagicMongoDBTool 。 Advanced Queries http://www.mongodb.org/display/DOCS/Advanced+Queries MapReduce http://www.mongodb.org/display/DOCS/MapReduce Aggregation http://www.mongodb.org/display/DOCS/Aggregation Unique Items with Map-Reduce http://cookbook.mongodb.org/patterns/unique_items_map_reduce/ 来源： https://www

How to find documents with unique values in MongoDB?

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问题 I have a collection with several documents in it of jobs to process using another system. I look up 5 objects from this table like this: Work.find({status: 'new'}) .sort({priority: 'desc'}) .limit(5) .exec(function (err, work){}) There is another field on these documents which determines that only one job with a given unique value can be ran at the same time. For example these 3 jobs: {uniqueVal: 1, priority: 1, type: "scrape", status:"new"} {uniqueVal: 1, priority: 1, type: "scrape", status:

DocumentDB find deep key:value

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问题 in MongoDB I can perform a find on any deep level key like collection.find('persons.age': 12) Is a similar thing possible with document DB? I have tried something like the following which fails with: code":"BadRequest" - could not be resolved. query: "SELECT * FROM root WHERE person.age = 12" 回答1: You must reference the collection from the FROM clause. Note: Since you are issuing queries directly to a collection, you can use any arbitrary value for the name. However, you must re-use whatever

Does firestore support skip functionality? [duplicate]

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问题 This question already has answers here : Pagination in firestore api (2 answers) Closed last year . Summary: I want to use the 'skip' function used in MySql and MongoDb. However, 'startAfter (number)' does not skip. I am making a bulletin board now. Then I got a question. This is a matter of page skip. I use the basic method of moving pages directly to users. However, I could not find any skip functions that Mysql or MongoDB used in the past. This is part of my code. return db.collection(

hierarchy property in graph database

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问题 I'm starting to use neo4j. In my graph database I've the nodes Person (look at "John" below), with the labels: Name (string), Food (positive integer). Each Person is connected with other Person through the relationship isFriendTo , that has a value. I use the graph DB only to find the shortest weighted path between two person. Also, every day I check every node in the graph, and if the food go under value of 100, I take some actions. Now, after some improvements, the property Food is no more

How to get array of document using Mongodb java?

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问题 How to get all the document under array in mongodb java. My Database is as below. Want to retrieve all the data under array 198_168_1_134 . below is some of What i tried, eventlist.find(new BasicDBObject("$match","192_168_10_17")) eventlist.find(new BasicDBObject("$elemMatch","192_168_10_17")) eventlist.find(null, new BasicDBObject("$192_168_10_17", 1)) 回答1: You have two options: using .find() with cherry-picking which document you have to have fetched. using the aggregation framework by

mongoDB : multi value field search ignoring null fields

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问题 I am trying to make a search on several field where some of them can be left blank. Given the following Json document in MongoDB (only three fields here, but N fields in reality, with N > 10) : { 'first_name' : 'value_X', 'last_name' : 'value_Y', 'mail_adress' : 'value_Z' } Then let's suppose a form where the user can enter the value of the first name, last name, mail address and phone number. If all the field are filled the query in MongoDB looks like : db.collection.find( { 'first_name' :

Tag driven database for asynchron BI

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问题 I'm having a little problem coming up with an architecture for tag driven software I'm designing. What I want to do is store plain text in database, which is liked to an owner and other entities. The plain text is filled with tags just like Twitters hashtags and should be searchable/indexable. That can be done application side and as a result I'm gonna have tons of small chunks of data that need to be processed for business intelligens. No one is gonna ready the plain text it's only about the

Big Data or relational database (like MySQL cluster)?

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问题 I am going to deal with a huge amount of data in my project. I have read about big data concepts but never used it yet. But reading all those Big Data Documents I am still not sure whether my requirement needs Big Data or is it good to handle with traditional relational database. Here is some information about my DB. My main DB is a repository for different data sources. Each of this data sources deals with same kind of data (data in same domain), but some data sources contain extra fields