Realm

View Current Viewing Revision #4 from 12/09/2018 3:16 p.m.

Realm is a an open-source and object-oriented DBMS, which is built for the mobile platform. It supports programming language including Objective-C, Swift, Java, Kotlin, C# and Javascript. It's built on zero-copy architecture, which could provide high speed and auto-updating results for the query.

History

Realm originates from the project called TightDB which was initially developed by Alexander Stigsen and Bjarne Christiansen began in the end of 2010. The first version of Realm was released in June 2016 and a platform for real-time two-way synchronization in beta version was released in 2016 September.

Query Compilation

Not Supported

Foreign Keys

Supported

Not Supported

Realm only maintains the log for the transaction. But it doesn't support the recovery mechanism.

Stored Procedures

Not Supported

Views

Virtual Views Materialized Views

Realm database supports reflective views and imperative views. Essentially they are very similar to materialized views and virtual views.

Concurrency Control

Multi-version Concurrency Control (MVCC)

In Realm, each connected thread will see a snapshot of the data at a particular point in time. Moreover, it utilizes the copy-on-write mechanism and allows only one client to modify data at a certain point.