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GPL licensed object database


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db4o Object Database

  • Native to Java and .NET
  • 100% object-oriented, no object-relational mapping
  • Designed for embedded use
  • Open source and free under the GPL


The Headstart You Need on Your Development Time.

Embed db4o's native Java and .NET object 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 simply as they are, without the tedious mapping overhead of relational databases.


        "I believe I shaved at least four months worth of development using db4o's object database approach, as I know how long it takes to engineer the equivalent solution using traditional technology...
        Before I settled for db4o, I evaluated Apache Derby, MySQL, Daffodil One$DB, Sqlite, and Berkeley."

                --David Tran, Transcraft

        "For our environment, db4o's open source database offers a much better fit compared to the alternative of a relational database plus an object-relational mapper.
        db4o runs up to four times faster persisting object data, and up to 50% faster querying for objects.

                --Sean DeMartino, INTEL

        "I'm very pleased! db4o is truly powerful and *insanely* easy to use..."
                --Zambizzi, User



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