[MongoDB]: Database References
MongoDB does not support joins. In MongoDB some data is denormalized, or stored with related data in documents to remove the need for joins. However, in some cases it makes sense to store related information in separate documents, typically in different…
[MongoDB]: Selecting a Shard Key for MongoDB
On Selecting a Shard Key for MongoDB – Bad-Ass Unicorn One of the killer features of MongoDB is the built-in sharding capabilities. This feature lets you spread out both your data, and your database workload, over multiple commodity-scale machines. While…
![[MongoDB]: Shard keys](https://dbversity.com/wp-content/uploads/2015/01/sharding-range-based-150x150.png)
[MongoDB]: Shard keys
Shard Keys¶ The shard key determines the distribution of the collection’s documents among the cluster’s shards. The shard key is either an indexed field or an indexed compound field that exists in every document in the collection. MongoDB partitions data…
[MongoDB]: How to use Write Concerns
This post describe on how to use write concerns in MongoDB and how it impacts durability, performance and resiliency. Write Concerns: This describes the level of concern or guarantee the server will provide in its response to a write operation….
[MongoDB]: Why we need odd number nodes in RS
The voting is done by a majority of voting members. Imagine a Replica Set with three (voting) members. Let’s say that Node A is primary, and nodes B+C are secondaries. Node A goes down, so nodes B+C go to election….
kill -9 in MongoDB !??
Memory-Mapped Persistence But let me start at the beginning, MongoDB’s persistence cycle, and then get to what’s being done to improve its reliability and your data’s durability. At the very heart, MongoDB uses memory-mapped files to store data. A memory-mapped…
RDBMS -Feature Comparision
Oracle vs Postgres vs SQLServer vs MySQL vs IBM-DB2 vs Firebird vs H2 HSQLDB vs Derby vs SQLite This comparison focuses on features that can be used in SQL statements or self-contained SQL scripts that don’t require additional software (e.g….
[MongoDB]: HOW DOES MONGODB WORK?
What is MongoDB? MongoDB is the database for today’s applications: innovative, fast time-to-market, globally scalable, reliable, and inexpensive to operate. With MongoDB, you can build applications that were never possible with traditional relational databases. Here’s how. Fast, Iterative Development. Scope…
[MongoDB]: MongoDB 2.6
MongoDB 2.6 MongoDB 2.6 has Key features include aggregation enhancements, text-search integration, query-engine improvements, a new write-operation protocol, and security enhancements. MMS 1.4, which includes On-Prem Backup in addition to Monitoring, is now also available. See MMS 1.4 documentation and the…
[ RDBMS to MongoDB ] Best practices for Migration
Relational databases are being pushed beyond their limits because of the way we build and run applications today, coupled with growth in data sources and user loads. To address these challenges, many companies, such as MTV and Cisco have migrated…