mongo: efficiently retaining only the most recent N duplicate records

mongo: efficiently retaining only the most recent N duplicate - I have got a bad feeling I am missing something really important here and should prolly sober up before I decide to try and program but:- Ok so given you have a

java - Mongo DB / No duplicates - You should look on Distinct function. Here you can find details with Spring.

Things I wish I knew about MongoDB a year ago - I've used MongoDB for over a year at scale at both Heyzap and You could store the aggregated count in mongo itself using the $inc command when inserting a new same query twice if you only have two values in your $in statement or Number of documents matched "n" : 3 , // Duration in milliseconds

Fast paging with MongoDB - Paging through your data is one of the most common operations with The skip( n) directive tells MongoDB that it should skip 'n' results, and the limit(n) directive instructs MongoDB Also, this process does not make efficient use of the indexes. Retrieve the _id of the last document in the current page 2.

$last (aggregation) - Only meaningful when documents are in a defined order. When using $last in a $group stage, the $group stage should follow a $sort stage to have the input

MongoDB Atlas Best Practices: Part 3 - *Figure 1: Create a sharded MongoDB Atlas cluster in just a few clicks* Range- based sharding: Documents are partitioned across shards ensuring only the most suitable secondary member is promoted to have applied the most recent updates from the primary and heartbeat and connectivity status.

Questions for mongodb - Are arrays in MongoDB documents always kept in order? 4867 mongo: efficiently retaining only the most recent N duplicate records. 8491

MongoDB: The Good, The Bad, and The Ugly - For those who are new to MongoDB, it's a NoSQL-Document a child of an object and it keeps going for 'n' levels), the MongoDB Though speed is advertised as a big plus of MongoDB, it is achievable only if you have the right indexes. Updating this duplicate data can be hard and, also due to lack of

Finding Duplicate Documents in MongoDB - Need to find duplicate documents in your MongoDB database? of Texas", " Closing Date" : "27-Jan-17", "Updated Date" : "17-Feb-17" }. Each document is provided with a unique ObjectId by MongoDB and also a unique CERT Running the aggregation using only the $group pipeline operator, we'll get

Collection() - Inserts a single document or a an array of documents into MongoDB. . db = new Db('test', new Server('localhost', 27017)); // Only run the rest of the code if we have result) { // Count the number of documents left (should not include the duplicates) .. use atomic operators and update instead for more efficient operations.

remove duplicate records in mongodb

Removing Duplicates from MongoDB - If you are certain that the source_references.key identifies duplicate records, you can ensure a unique index with the dropDups:true index

How to remove duplicates based on a key in Mongodb? - If you ever find yourself in a position where you need to remove duplicate entries on a MongoDB collection, as per version 3.0 you will need to

How To Remove Duplicates In MongoDB - Duplicate records can be removed from a MongoDB collection by creating a unique index on the collection and specifying the dropDups option. Assuming the collection includes a field named record_id that uniquely identifies a record in the collection, the command to use to create a unique index and drop duplicates is:

Finding Duplicate Documents in MongoDB - Need to find duplicate documents in your MongoDB database? .. with more than one document allows for a lot of the noise to be removed.

dropDups() Method To Remove Duplicate Documents: MongoDB - Duplicate records can be removed from a MongoDB collection by creating a unique index on the collection and specifying the dropDups option.

How to delete duplicate values in the following mongodb collection - As of version 2.x, MongoDB dropped support for dropDups due to it's We want to remove all duplicates that have the same combination of

Remove duplicates from MongoDB - MongoDB dropDups option in Index creation will be useful to remove duplicate records that already exist in the collection. > use foo. switched

[MongoDB]: dropDups to remove duplicate records : - db.collection.deleteMany() db.collection.drop() →. © MongoDB, Inc 2008-present . MongoDB, Mongo, and the leaf logo are registered trademarks of MongoDB,

db.collection.distinct() - While MongoDB supports an option to drop duplicates, dropDups, during index and record (in the uniqueIds field) each _id value of the grouped documents.

Finding Duplicate Keys with MongoDB's Aggregation Framework - http://technotip.com/4215/remove-duplicate-documents-mongodb/ lets see key when there

mongodb find duplicate values

Finding Duplicate Documents in MongoDB - You can find duplicate values within your MongoDB database using the aggregate method along with the $group and $match aggregation pipeline operators.

Find duplicate records in MongoDB - Use aggregation on name and get name with count > 1 : db.collection.aggregate( {"$group" : { "_id": "$name", "count": { "$sum": 1 } } }

MongoDB: find duplicates in a field (Example) - This little script helps find duplicated data in a MongoDB field. mapReduce(m,r, { out : "my_output" }); db[res.result].find({value: {$gt: 1}});

Find duplicate records in MongoDB - You can use the aggregate framework to find duplicate records in MongoDB. To understand the concept, let us create a collection with the

db.collection.distinct() - Finds the distinct values for a specified field across a single collection or view find with a sort, you cannot use one collation for the find and another for the sort.

Finding duplicate keys with MongoDB's aggregation framework - Use the MongoDB aggregation pipeline framework to avoid blindly some form of the following error because of duplicate key value(s):.

Finding Duplicate Keys with MongoDB's Aggregation Framework - some form of the following error because of duplicate key value(s):E11000 First, find and copy your MongoDB connection string from the cluster details

Finding duplicates in MongoDB via the shell – WiredPrairie - The summary is that you can use the power of MongoDB's aggregation framework to search and return the duplicates. It's really quite slick.

How To Remove Duplicates In MongoDB - You can find duplicate values within your MongoDB database using the aggregate method along with the $group and $match aggregation

MongoDB: How to check for duplicates in a collection - This techniques to find out dupes in a MongoDB collection uses Map the values of the field called myField, for each distinct value of myField,

mongodb find duplicates multiple fields

Mongo find duplicates for entries for two or more fields - You can easily identify the duplicates by running the following aggregation pipeline operation: db.collection.aggregate([ { "$group": { "_id":

Mongo find duplicates for - Need to find duplicate documents in your MongoDB database? In other words, MongoDB lets you select fields and group together We won't be looking for duplicate Bank Name s since a bank can have multiple branches

Finding Duplicate Documents in MongoDB - Use the MongoDB aggregation pipeline framework to avoid blindly deleting data and to Example aggregation query to identify duplicate keys and record (in the uniqueIds field) each _id value of the grouped documents.

Finding duplicate keys with MongoDB's aggregation framework - Example aggregation query to identify duplicate keys index key values and record (in the uniqueIds field) each _id value of the grouped documents. .. There are also multiple driver timeouts that can be tweaked based on the exact behavior

Finding Duplicate Keys with MongoDB's Aggregation Framework - You cannot specify multiple collations for an operation. For example, you cannot specify different collations per field, or if performing a find with a sort, you cannot

db.collection.distinct() - Above query find all the duplicates elements whose account, vendor , category category : "$category"}, // can be grouped on multiple properties/keys/columns Enjoy the MongoDB and the brilliant Aggregation Framework !

Aggregation Framework - You could group by email and find out who is using your service most often. to do this: http://docs.mongodb.org/manual/reference/operator/aggregation/cond/. For example, say you have a dataset containing duplicate emails, you might want It scales beautifully by sharding your data across multiple commodity servers,

Counting distinct fields with $project and $match - The four records have three distinct values for the first_name field (“mike, “william ”, and Removing Duplicates from MongoDBIn "Database".

“Count” and “Count Distinct” Queries in MongoDB - This tutorial will teach you how to find these duplicate rows. two columns to be unique together, or are you simply searching for duplicates in a single column?