AtCoder vs. Codeforces vs. ShortStack vs. ThinkSQL Comparison Chart

Codeforces is a project joining people interested in and taking part in programming contests. On one hand, Codeforces is a social network dedicated to programming and programming contests. On the other hand, it is a platform where contests are held regularly, the participant's skills are reflected by their rating and the former contests can be used to prepare. Codeforces constantly develops and we plan to improve the platform to give the participants the opportunity to organize their own contests, filling the project with learning content, developing Codeforces as a training and learning platform. Contests are regularly held on Codeforces. Participating in them is free and open to everybody. Every month we organize approximately six contests. To participate, you have to be registered on the site (if you have an OpenID or a Gmail account, then you won't even have to memorize the password) and register for the oncoming contest. Make sure that you are present in the list of the users.

ThinkSQL is a powerful, cross-platform relational database management system designed for modern operating systems and hardware. It aims to comply fully with the ISO SQL standard to provide an open and flexible SQL server for your applications. Compliance with the SQL standard means it supports transactions, sub-selects, views, set operators (union, except, intersect), access privileges and comprehensive referential constraints to ensure the integrity of your data. ThinkSQL uses a multi-versioning engine to provide consistent views of data and concurrent access to rows without locking. The server also has stored procedures and functions (using the standard syntax), and has support for large multimedia objects. It's easy to install, runs on Windows ® and Linux ®, and has native ODBC, JDBC™, dbExpress™ and Python drivers so your applications can connect directly from any platform.