Introduction to OrientDB

OrientDB is an open source NoSQL database management system. NoSQL databases provide a mechanism for storing and retrieving non-relational or non-relational data that refers to data other than tabular data, such as document data or graph data. Big data and real-time web applications increasingly use NoSQL databases. NoSQL systems are sometimes called "Not Only SQL" to emphasize that they may support SQL-like query languages.

OrientDB also belongs to the NoSQL series. OrientDB is a second-generation distributed graph database with flexible document capabilities in one product, and is released using the open Apache 2 license. Before OrientDB there were several NoSQL databases on the market, one of them was MongoDB.

MongoDB vs. OrientDB

MongoDB and OrientDB contain many common features, but the engines are fundamentally different. MongoDB is a pure document database, and OrientDB is a hybrid document with a graph engine.

Features:

Relationships

MongoDB uses RDBMS JOINS to create relationships between entities. It has a high runtime cost and does not scale as the database size increases.

OrientDB uses a relational database to connect and connect documents. It uses direct, ultra-fast links from the world of graph databases.

Get plan

MongoDB expensive JOIN operation.

OrientDB easily returns complete graphs with interconnected files.

Transaction

MongoDB does not support ACID transactions, but it supports atomic operations.

OrientDB supports ACID transactions and atomic operations.

Query Language

MongoDB has its own language based on JSON.

OrientDB query language is built on SQL.

Index

MongoDB uses the B-Tree algorithm for all indexes.

OrientDB supports three different indexing algorithms so that users can get the best performance.

Storage engine

MongoDB uses memory mapping technology.

OrientDB uses the storage engine names LOCAL and PLOCAL.​

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