H-Store

NewSQL

H-Store was an experimental database management system designed for on-line transaction processing applications.

History

H-Store was originally conceived as the academic prototype. The original version of H-Store was a single-node proof-of-concept used in the 2007 VLDB paper. In the beginning of 2008, researchers at Brown, MIT, and Yale started working on a full-fledged, general purpose H-Store system. At the same time, Horizontica was launched as an secret internal project at Vertica. Once again, these were separate code bases that were to serve separate purposes.

In the spring of 2008, it was decided to merge together the backend execution engine of H-Store and the front-end transaction coordinator and query planner of Horizontica. After the VLDB demo in the fall of 2008, the H-Store codebase was forked off and became VoltDB.

The final version was announced in 2016. There have been no new developments since then. The code

Checkpoints

Consistent

Concurrency Control

Deterministic Concurrency Control

Data Model

Relational

Isolation Levels

Serializable

All transactions execute with SERIALIZABLE isolation. It is not possible to execute transactions at a lower isolation level.

Logging

Command Logging

Query Compilation

Not Supported

Query Execution

Materialized Model

Query Interface

SQL Stored Procedures

The primary query interface for H-Store was through stored procedures written in Java.

Storage Architecture

In-Memory

Storage Organization

Heaps

Stored Procedures

Supported

All transactions are executed as Java-based stored procedures.

System Architecture

Shared-Nothing

Views

Virtual Views

H-Store only supports simplistic views based on aggregations (e.g., COUNT, SUM).

H-Store Logo
Website

https://hstore.cs.brown.edu/

Source Code

https://github.com/apavlo/h-store

Tech Docs

https://hstore.cs.brown.edu/documentation/

Developer

Brown University, Massachusetts Institute of Technology, Carnegie Mellon University

Country of Origin

US

Start Year

2006

End Year

2016

Former Name

Horizontica

Project Type

Academic, Open Source

Written in

C++, Java

Derived From

HyperSQL

Operating Systems

Linux

Licenses

BSD, GPL v3

Wikipedia

https://en.wikipedia.org/wiki/H-Store