@rkenmi - Search Results

NoSQL - the Radical Databases

NoSQL NoSQL is a category of databases that aren't relational. For example, MySQL would be a relational database, where as MongoDB would be a NoSQL database. Back then, relational databases were the tried-and-true, prevalent and reliable data stores.

December 31, 2020

Design Concepts

... columnar databases (similar to MySQL and tabled data), document based storage (MongoDB) or key-value stores (DynamoDB). Key-Value Stores: Data is stored in an array of key-value pairs.

November 20, 2019

A primer on MapReduce

... essentially synonymous with the functional programming map. A mapper function is used to take a key-value pair and transform them into the desired data format. During the map stage, the master planner will keep track of which split (basically a piece of the file to process) is handled by which worker, using its own map meta-table.

July 11, 2020

Comparison Charts of File Storage Formats

Big Data Encodings These encodings are often used with HDFS or some other distributed file system. Since the data can be as large as terabytes or petabytes, it is crucial to encode files in a space optimal way and also allow themselves to be read or written in an optimal way.

January 24, 2022

Sharding Techniques

... available for sharding. \(hash(key)\;\%\;N\;=\;D\), where \(D\) is the machine to store the key-value of the database row. Pros: Simple to implement Cons: Things can fall apart when the number of machines \(N\) increases or decreases.

July 31, 2020

Local Secondary Index vs. Global Secondary Index

... be an expensive and time-consuming operation. Another database with LSI support is DynamoDB, a key-value database. Conceptually, DynamoDB's partition key / sort key combination for LSIs make sense.

January 15, 2022