VoltDB Blog » Douglas Patten

Leaderboards: Optimization for Ranking-Related Queries

Douglas Patten — Fri, 05 Oct 2012 18:07:09 +0000

My name is Xin Jia and I was one of the student interns at VoltDB this summer. For one of my projects, I worked on a feature that greatly improved the performance of ranking-related queries.

Finding the rank of an entry in a sorted list of data is a common operation in a lot of applications. Take a leaderboard within gaming application as an example: it is common to have a scoreboard that keeps track of users’ scores. Questions like, “what are the top-n users and their corresponding scores?”, or “what is the rank of a certain user?” are … Read more

VoltDB Explain Plan Command and Planner Testing Tool

Douglas Patten — Wed, 12 Sep 2012 17:33:13 +0000

My name is Zheng Li, a UMass Lowell graduate student. I spent the summer as an internship at VoltDB. Over the summer, I primarily worked on two VoltDB features, both related to query plans. The features are:

Explain plan command
Planner testing tool

A query plan is an ordered set of steps used to access or modify information in a SQL relational database management system (see http ://en .wikipedia .org /wiki /Query _plan). Understanding query plans is important because the first plan chosen to execute will directly affect the query execution time. Both … Read more

VoltDB – Simplified CSV Loader

Douglas Patten — Thu, 23 Aug 2012 17:21:09 +0000

My name is Xin Jia, a Brown University student, and I’ve spent the summer interning at VoltDB. One of the first projects that I worked on this summer was a CSV Loader with fellow intern Zheng Li.

Prior to VoltDB 2.8, loading data from CSV files into the database could be a challenging task, especially for newcomers. There were a few steps that needed to be taken: you would need to write a client program to parse the CSV data, handle errors and ultimately invoke a stored procedure to insert the data into the database. Extra care needed to be … Read more