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GPL licensed C# database


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db4o C# Database

  • Native to .NET 2 and 3.5 (including the Compact Framework)
  • 100% object-oriented, no object-relational mapping
  • Designed for embedded use in zero-admin environments
  • Open source and free under the GPL


The Headstart You Need on Your Development Time.

Embed db4o's native C# database engine into your product and store even the most complex object structures with only one line of code!

db4o slashes development cost and time, provides superior performance, and requires no DBA.

Download and test drive the world's most popular object database! It's free and open source under the GPL, no registration is required!

RDBMS Object-Relational Mapping vs. db4o

Store objects just as they are, without the tedious O/R mapping overhead.


"Our biggest concern is shortening our commissioning time. The use of db4o on the data-backend has helped us to achieve a time-saving effect of at least 10% on each project"
                --Sebastian Hubrich, BOSCH Sigpack

"With db4o, we can significantly reduce our development costs, improve time to market, and maintain the highest quality. Without db4o's ease of use we would be still struggling with SQL code and trying to get our product to work."
                --Ilpo Juvander, Juvander Consulting

        "db4o, a great, open source, OODB that can beat SQL Server anytime when it comes to persisting native objects. No mapping, no nothing, store your object model, not a flat, relational model."
                --ThomasJ, Blogger



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