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Welcome to the Doradus wiki! Below are links to topics about Doradus. We'll add new articles, FAQs, and whatnot over time.

See the README file in the root folder for an overview of Doradus and general information such as how to build Doradus, dependencies, and how to start the server. More pages with client examples are coming -- links to these will be posted here.

General Information

• Doradus History: The Doradus Story
• Contributors: Doradus Contributors
• Doradus OLAP: Wiki Pages

Wiki pages for Doradus Spider and Doradus Administration are coming!

New in v2.2

We're proud to announce the release of Doradus version 2.2 (v2.2). Here's a summary of some of the new features available:

OLAP

• Several memory and performance improvements have been made, allowing data to be loaded faster with less memory. In one internal load test, we can load 1 billion objects at an average rate of 500,000 objects/second -- on a single node!
• New scalar types float and double have been added. Correspondingly, DQL has been updated to support floating-point types in equations.
• All scalar types can now be multi-valued.
• Several enhancements have been made to aggregate query functions including INCLUDE, EXCLUDE, TOP, and BOTTOM.
• Data batches can now specify Overwrite=false to prevent values from replacing existing values. (That is, all values are purely additive.)
• The aggregate query metric functions COUNT, MINCOUNT, and MAXCOUNT can now be used on scalar fields.
• The DISTINCT metric function is now supported.
• Link paths can now begin with a WHERE filter to narrow perspective objects or those passed to the corresponding metric function or grouping field. Such "zero-level filters" allow schema alias definitions to be used virtually anywhere in object and aggregate queries.
• Link field names and aggregate groups can be renamed in result documents using the AS function.
• The order parameter (&o) used in object queries can use link paths, which means results can be sorted by extended fields.
• Metric functions can now use the transitive operator (^). For example, the metric function COUNT(DirectReports^) counts all direct reports recursively down the org chart for each object.

Spider

• Many of the aggregate query improvements made for OLAP were also added to Spider, such as aggregate query functions enhancements for INCLUDE, EXCLUDE, TOP, and BOTTOM.

General

• Doradus is now tested with the Cassandra 2.0.x release. Tests show that upgrading Cassandra alone yields a roughly 6% improvement in load performance.
• Doradus now supports the CQL API for communication with Cassandra. See the Doradus Administrator documentation for configuration and caveats.
• The PDF documentation is now complemented by a growing base of online Wiki pages. This work is ongoing, but check out the Doradus OLAP Wiki pages, which are up-to-date for the v2.2 release.

More good stuff happening -- stay tuned!

License

Doradus uses the Apache License version 2.0. See LICENSE.txt or the Apache License page for details.

A number of open source third party libraries are also used. See NOTICE.txt for details.

Doradus is Copyright 2014, Dell Inc. For now, we're only allowing Doradus team members to push updates, but anyone can download, fork the code, and send pull requests.