Checkpoints

Not Supported

Stored Procedures

Not Supported

System Architecture

Embedded

Joins

Not Supported

NeDB does not support joins because it is not a relational database but rather a document store database. Additionally, MongoDB does support Joins, but this feature of MongoDB is not one that was also implemented in NeDB.

Concurrency Control

Not Supported

NeDB does not support currency because each process receives it's own copy of the database and there is no way to sync the views that two separate processes have of the database. Additionally, Javascript is inherently single-threaded resulting in no concurrency.

Indexes

AVL-Tree

NeDB supports indexing and helps provide a sufficient speed boost. It allows for indexing of any field, including those in nested documents. An index can be created at any point, even after data has been inserted, although it is most efficient if done when the application is started because the index is created synchronously. The time to create an index is quite fast so it doesn't impact startup time too much, for example it takes 35ms for a database containing 10,000 documents. Additionally, indexes allow for the database to perform fast reads and writes. The amount is approximately 5,000 writes and 25,000 reads per second.

Storage Architecture

In-Memory

The DBMS reads the entire database into memory. It can then flush out all changes on shutdown.

Data Model

Document / XML

Query Interface

Custom API

The JavaScript API is a subset of MongoDB.

Storage Organization

Heaps

Logging

Not Supported

NeDB does not support logging because all data is stored in memory. However, a NeDB logger has been created that can be used to insert documents into a NeDB-readable database.