July 28, 2015 The contest's final ranking and the finalists' solutions can be found here.
April 9, 2015 We just completed our evaluations. Congratulations to the following teams (in alphabetical order) for making it to the final round:
  • Crisis
  • CStrings
  • CUT_HERE________________
  • SimpleMind
  • Vika
See you in Melbourne, Australia!
March 8, 2015 We uploaded a new medium-sized dataset to allow you better offline testing, profiling and tuning.
February 18, 2015
(February 19 00:00 Pacific/Kiritimati)
The contest registration and submission system is now live. Happy programming!
February 12, 2015 We also added unofficial stub implementations for Java, Go and Rust on the task page. We do not guarantee their correctness. The C++ reference implementation is now also build with -O3 by default.
February 9, 2015 Follow us on twitter @sigmod15contest to get news about this year's contest.
February 9, 2015 Contest announced! Query details, a reference implementation with test driver and two test cases are available on the Task page.

Contest Overview

Student teams from degree-granting institutions are invited to compete in the annual SIGMOD programming contest. The task for this year's contest is focused on an aspect of optimistic concurrency control. The winning team will be awarded a prize of USD $5,000. Submissions will be judged based on their overall performance on a supplied workload. The top 5 submissions will receive a travel grant to attend SIGMOD 2015 in Melbourne, Australia.

Task Overview

The ACID principle, mandating atomicity, consistency, isolation and durability is one of the cornerstones of relational database management systems. In order to achieve the third principle, isolation, concurrent reads and writes must be handled carefully.

In practice, transaction processing is often done in an optimistic fashion, where queries and statements are processed first, and only at the commit point the system validates if there was a conflict between readers and writers.

In this challenge, we simulate this in a slightly simplified way: The system processes already executed transactions and only needs to check efficiently whether concurrent queries conflict with them.

Important Dates

February 9, 2015 Detailed specification of the requirements and test data available.
February 19, 2015 Team registration begins. Leaderboard available.
April 7, 2015, 23:59 GMT+2 Final submission deadline.
April 20, 2015 Finalists notified.
May 31, 2015 SIGMOD 2015 Conference begins.


Microsoft logo    Prize money for the winning team is gracefully donated by Microsoft.


Ask technical questions and stay up to date by joining the SIGMOD 2015 contest Google Group.
For non-technical questions, please e-mail