mongodb

问题 I'M trying to create a text index without a default language. The official docs specify If you specify a language value of "none", then the text search uses simple tokenization with no list of stop words and no stemming. Hence I tried: createIndex({aliases : "text"}, {name : "aliases_txt"}, {default_language: "none"}) However the created index ignores my option and has "english" as default language: { "v": 1, "key": { "_fts": "text", "_ftsx": 1 }, "name": "aliases_txt", "ns": "ner-dict.ents",

问题 i have a collection which has duplicate records. I am using mongodb 4.0. How do i remove the duplicate records from the entire collection? the record are getting inserted with the following structure { item: "journal", qty: 25, size:15 , status: "A" } All i need is to have unique records for one document. 回答1: You can group duplicated records using aggregation pipeline: db.theCollection.aggregate([ {$group: {_id: {item: "$item", qty: "$qty", size: "$size", status: "$status"}}}, {$project: {

问题 I have a mongo collection(s) with 2.5 million data and that may grow upto 3 million. I am using spring batch and am trying to copy that collection to another collection. Approaches I have used are as follows : Inside a tasklet, I have Created a ProcessBuilder object and called a shell script which executes a mongo query. Content of shell script is as follows : > mongo $serverURL/$dbName js-file-to-execute.js // js file contains copy command (db.collection.copyto('newCollection')) For less

问题 Heres what Im thinking. Do you see any issues with this workaround to emulate 2 phase commit when using something like MongoDB where each operation is atomic and there is no support for transactions outside of that? transaction_scope: read message from servicebus - UpdateCustomerAddress get customer aggregate from docdb, replay events where commited =1 call customer.updateAddress validates creates customer address updated event apply event event store as uncommitted events do optimistic

问题 Heres what Im thinking. Do you see any issues with this workaround to emulate 2 phase commit when using something like MongoDB where each operation is atomic and there is no support for transactions outside of that? transaction_scope: read message from servicebus - UpdateCustomerAddress get customer aggregate from docdb, replay events where commited =1 call customer.updateAddress validates creates customer address updated event apply event event store as uncommitted events do optimistic

问题 I'm writing a simple scala-based script which supposed to insert some data into Mongo collection. The problem is, that script exits before mongo finishes it's task. What is the idiomatic/best approach to deal with the problem, considering following script: #!/usr/bin/env scalas /*** scalaVersion := "2.12.2" libraryDependencies ++= { Seq( "org.mongodb.scala" %% "mongo-scala-driver" % "2.1.0" ) } */ import org.mongodb.scala._ val mongoClient: MongoClient = MongoClient("mongodb://localhost") val

问题 I was going thru bunch of mongo docs and can't find a possibility to shuffle or randomize result content is there any ? 回答1: Specifically for the aggregation framework itself there is not really any native way as there is no available operator as yet to do something like generate a random number. So whatever match you could possibly project a field to sort on would not be "truly random" for lack of a shifting seed value. The better approach is to "shuffle" the results as an array after the

问题 There is a huge collection with 600.000 documents. Unfortunatly there are duplicates, which I want to find. These duplicates differs only in first letter upper/lower case. { key: 'Find me' }, { key: 'find me' }, { key: 'Don't find me }, // just one document for this string { key: 'don't find me either } // just one document for this string Now I want to get all duplicates, which means there is an existing uppercase AND lowercase string. 回答1: In MongoDB, there is a $toLower transformation

问题 I would like to know how to execute a JavaScript file in MongoDB. This is the simple piece of code present in my JS file: function loadNames() { print("name"); } From the command prompt I tried to execute the file like this mongo test.js but it shows the error: unexpected identifier Can anyone explain to me where I'm going wrong? 回答1: I usually run my test queries like this, and it works with your sample code too. mongo < test.js 回答2: two meothods to achieve this: 1 . use " --eval " mongo

问题 I am working in a Java Spring environment and been having issues with getting @Qualifier to work. Other portions of our project are using @Inject to acquire a bean, but I need to have two versions of the same one and it looks like using @Autowired and @Qualifier should do the trick, but I cannot get them to work. I am probably missing one little thing, but haven't had any luck finding an answer. Here are the pertinent parts of the code. I have been trying out various things, so I probably