db4o is an [[oodbms|object database]], native to [[Java]] and

for [[.NET]], including [[CompactFramework]] and [[Mono]].

Features include [[ACID]] transactions, automatic

class schema recognition, [[Native Queries]], small footprint, and many more, that make it ideal for embedded use in devices, packaged software and realtime systems.

h3. External Links

* "Getting started with db4o with dbutil":http://www.spaceprogram.com/knowledge/2006/07/db4outil-aka-easiest-way-to-get.html db4o":http://www.spaceprogram.com/knowledge/2006/07/db4outil-aka-easiest-way-to-get.html

db4o is an [[oodbms|object database]], native to [[Java]] and

for [[.NET]], including [[CompactFramework]] and [[Mono]].

Features include [[ACID]] transactions, automatic

class schema recognition, [[Native Queries]], small footprint, and many more, that make it ideal for embedded use in devices, packaged software and realtime systems.

h3. External Links

* "Getting started with db4o":http://www.spaceprogram.com/knowledge/2006/07/db4outil-aka-easiest-way-to-get.html

db4o is an [[oodbms|object [[object database]], native to [[Java]] and

for [[.NET]], including [[CompactFramework]] and [[Mono]].

Features include [[ACID]] transactions, automatic

class schema recognition, [[Native Queries]], small footprint, and many more, that make it ideal for embedded use in devices, packaged software and realtime systems.

db4o is an [[object database]], native to database]] available for [[Java]] and

for [[.NET]], including [[CompactFramework]] and [[Mono]].

Features include [[ACID]] transactions, automatic

class schema recognition, [[Native Queries]], small footprint, and many more, that make it ideal for embedded use in devices, packaged software and realtime systems. query-by-example,

[[S.O.D.A]].

db4objects is proud to announce the release of db4o production version 5.2.002, which is available for immediate, free download from the "db4o db4o Community Zone":http://www.db4o.com/community/. Zone.

db4o version 5.2 comes with up to 300% improved performance as well as plenty of new APIs for Native and sorted queries to improve developer productivity -- and thus underlines db4o's position as the most native Java and .NET database available today.

IMPROVED PERFORMANCE: In response and cooperation with our users, db4objects has improved its insert and delete performance massively since earlier version 5 releases. The time to store 100,000 simple objects has been cut by 4x. The insert performance, which had been suffering in V5.0 (with FlushFileBuffers = on) from a design trade-off in favor of more reliable file-flushing, has not only been restored to V4.5's level (where the operating system's unpredictable file flushing sequence could have corrupted db4o database files in rare cases of power failure in the midst of a transaction), but is now better than ever -- e.g. 20% faster for deeply structured object inserts.

Storage properties are the critical factor for performance. On standard off-the-shelf hardware ( P4 3Ghz, 7000 RPM SATA ) db4o stores 14,000 objects per second. When using a memory IO adapter, the speed increases to 25,000 objects per second (see Poleposition Melbourne benchmark). And when used in in-memory mode, db4o is once again faster by orders of magnitude and has, for instance, been deployed in mission critical real-time control systems to store 200,000 objects per seconds.

NATIVE QUERIES: The widely acclaimed db4o Native Query Engine has been enhanced to provide optimized execution speed for more use-cases, such as:

* String#startsWith()

* String#endsWith()

* String#contains()

* Static member access and method calls

* Array access for non-candidate based fields

* Arbitrary method calls on non-candidate based fields

An example with #startsWith optimisation would look as follows:

IList employees = db.Query(delegate(Employee e)

{

return e.FirstName.StartsWith("P");

});

Since Version 5 db4o supports Native Queries to express database queries in native semantics of the programming language, e.g., in Java, C#, or VB.NET. This makes development significantly more productive than using incumbent string-based APIs (such as SQL, JDO, OQL), because developers have 100% typesafe, 100% refactorable, and 100% object-oriented access to their data layer.

SORTED QUERIES: We have listened to our users' most requested feature and now provide a new interface to sort query results. The interface is compatible to the standard way sorting is typically done on Java and .NET platforms: The query engines now accepts passing a normal java.util.Comparator / System.Collections.IComparer object, allowing for true object-oriented sorting with any degree of complexity. This fosters db4objects' goal to provide to most native persistence solution on the market. The new sorting mechanism can be used for both, Native Queries and SODA queries.

NEW MONO PASCAL CASE DISTRIBUTION: For our fast growing db4o for Mono user community, we have now prepared a new API with PascalCase naming for better compliance with the framework guidelines. This API is standard to the general Mono download from the db4o Community Zone with V5.2.002 or higher. An assembly with the old camelCase API is still provided, but users are encouraged to migrate to the new API as soon as possible. You find the old API in a directory labelled 'legacy' in db4o's installation folder, after you have unpacked/installed the provided tarball/RPM package of V5.2.

=db4o REPLICATION SYSTEM (dRS) UPDATED TO V1.1=

The dRS has been updated to incorporate the first round of user and customer feedback and is now available as a development version 1.1 for free download from the db4o Download Center.

Specifically, dRS version 1.1 can now fully support Collections and replicate them bi-directionally. Also, a series of user change requests as documented in Bugzilla has been resolved, partly by updating the underlying engine to Hibernate V3.1.2.

Thanks to the massive usage and testing through db4o's large user community on a multitude of platforms, the dRS has been made even better compatibility with the RDBMSs MySQL, Postgresql and Oracle 9i.

The db4o Replication System (dRS), first released in January 2006 and powered by Hibernate, enables users to build applications that synchronize objects bi-directionally between distributed instances of db4o's object database, all common relational databases such as Oracle or MySQL, and any combination thereof.

-- VERSION 5.0 WITH NATIVE QUERIES AVAILABLE --

We're proud to announce availability of db4o Version 5.0 for Java and .NET, introducing "Native Queries," which express database queries in native semantics of the programming language. This eliminates the need for developers to learn additional non-mainstream APIs such as JDO, OQL, or SODA and initiates a new level of productivity for writing truly object-oriented software applications. db4o Version 5.0 is available as a production-ready version for free download.

Native Queries (NQ) reflect the current industry trend to construct data access as a native part of the object-oriented application, rather than using string-based, non-native access. Thus they put an end to the 15-year-long debate about which additional query language to use in creating an OO query API. NQs simply use the existing, widely adopted standard - the programming language itself - to access the database. As the first player to endorse this simple yet groundbreaking concept, db4objects underlines its leadership in providing the most native, object-oriented persistence solution on the market.

Native Queries are based on Safe Queries as proposed by Prof. William Cook at the 27th International Conference on Software Engineering (ICSE) in May of 2005. The concept of compliance with existing standards eliminates the need for new standards such as ODMG's OQL and Java's JDO1, which have been disbanded and/or failed to see mass adoption. NQs thus remove a major roadblock for mainstream adoption of object-oriented persistence solutions (object databases, object-relational mappers) - similar to what SQL did for relational databases.

"With Version 5, db4objects is pushing the seamless object-oriented development experience even further," says Stephen O'Grady, senior analyst at Redmonk. "When developers are not required to transition out of an object oriented environment and the language of their choice, they're likely to be far more productive. Consequently, several vendors - including Microsoft with its LINQ project - are seeking to break down the barriers between non-native APIs and the programming language on top of it, by allowing querying in native language - an approach that could become popular to access databases from OO programming environments."

db4o Version 5's Native Queries express database queries in native semantics of the programming language, e.g., in Java, C#, or VB.NET. This makes development significantly more productive than using incumbent string-based APIs (such as SQL, JDO, OQL), because developers have 100% typesafe, 100% refactorable, and 100% object-oriented access to their data layer.

db4o is an [[object database]] object database available for [[Java]] Java and

for [[.NET]], .NET, including [[CompactFramework]] CompactFramework and [[Mono]]. Mono.

Features include [[ACID]] ACID transactions, automatic

class schema recognition, query-by-example,

[[S.O.D.A]]. S.O.D.A.

db4o is an object database available for Java and

for .NET, including CompactFramework and Mono.

Features include ACID transactions, automatic

class schema recognition, query-by-example,

S.O.D.A.