QED

QED is a pure Java database that features:

• Pure Java: a high performance, small footprint, zero-administration database, perfect for embedding with your application.
• A full set of RDBMS features: transactions, data integrity, failure recovery, comprehensive SQL 92 conformance plus many SQL3 features.
• Support for JDBC 2.0
• Open source, free software! No license fees, no restrictions!
• QED's pure Java engine provides very high performance, since database accesses can be performed locally, without the necessity of a network round trip for every
• operation. Conventional JDBC drivers, no matter how fast the back-end database, incur network overhead -- frequently the bottleneck in a database application. A
• configurable in-memory cache also helps boost performance by reducing disk operations.
  

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