Trafodion

Trafodion is an open-source webscale SQL-on-Hadoop DBMS solution that extends and builds on Apache Hadoop. Its name is the Welsh word for "transactions" (pronounced "Tra-vod-eee-on") because the developers wanted to emphasize the fact that one specific way it extended Hadoop was through guaranteed transactional integrity. By doing so, it targets big data transactional and operational workloads rather than analytic workloads. It is ACID-compliant and has fully-functional ANSI SQL support

History

Hewlett-Packard Company launched Trafodion as an open-source project in 2014, and a version was released in early 2015 before it became a part of the Apache Incubator in May 2015. In January of 2018, it was established as an Apache Top-Level Project.

Concurrency Control

Multi-version Concurrency Control (MVCC)

Apache Trafodion utilizes the HBase-Trx implementation of Multi-version Concurrency Control (MVCC). This implementation guarantees row-level ACID semantics and only requires row locks for write operations, not read operations.

Data Model

Column Family

Since Trafodion is built on top of HBase, it shares HBase's column family data model using key-value pairs.

Foreign Keys

Supported

Foreign key constraints are supported in Trafodion.

Isolation Levels

Read Committed

Trafodion only supports the READ COMMITTED isolation level.

Joins

Hash Join

Trafodion supports hash joins. It is recommended that the number of tables in a join is limited to 64, otherwise the query may not compile.

Logging

Logical Logging

Trafodion utilizes HBase's Write Ahead Log.

Query Interface

SQL

Trafodion fully supports ANSI SQL.

Storage Architecture

Disk-oriented

Trafodion is built on top of HBase, which means it shares its disk-oriented storage architecture model from HDFS.

Storage Model

Decomposition Storage Model (Columnar)

Trafodion uses a single column family to store all columns.

Stored Procedures

Supported

Trafodion allows for stored procedures written in Java and typically compiles with SQL and JRT (Java Routines and Types). The stored procedure itself is a Java method in a JAR file.

Trafodion Logo
Website

https://trafodion.apache.org/

Source Code

https://github.com/apache/trafodion

Tech Docs

https://trafodion.apache.org/documentation.html

Developer

Hewlett-Packard Company

Country of Origin

US

Start Year

2014

Acquired By

Apache Software Foundation

Project Type

Open Source

Written in

C++, Java

Supported languages

SQL

Derived From

HBase

Operating Systems

Linux

Licenses

Apache v2

Wikipedia

https://en.wikipedia.org/wiki/Apache_Trafodion