Category Archives: DataNucleus

JDO 3.2 JDOQLTypedQuery

JDO 3.2 is now standardising what we initially developed as a DataNucleus extension for JDO querying, namely typesafe queries. In DataNucleus upto and including v4.1 it was referred to as JDOQL Typesafe Query, and in JDO 3.2 (DataNucleus v4.2+) it … Continue reading

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Configuring persistence of fields/properties using TypeConverters with JDO

JPA 2.1 allows a user to specify a converter on the value of a field/property for how it is persisted in the datastore. The way we implement that in DataNucleus is to have the JPA converter as a wrapper to … Continue reading

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AccessPlatform 2.0 will arrive soon

… just until the 9th January 2010 to wait. The result of 10 months of restructuring and extensions to DataNucleus, extending the capabilities and simplifying the process of adding on new datastore support for many things.

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"JPQL2" becomes the default JPQL implementation for RDBMS

The rewrite of JPQL for RDBMS, formerly known as “JPQL2” is now the default JPQL implementation in DataNucleus SVN trunk. It passes the JPA TCK completely, and so no reason not to swap over to using it now. So if … Continue reading

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As mentioned earlier DataNucleus querying capabilities are being progressively rewritten, making use of a “generic” query compilation. In the previous post I mentioned a new implementation of JDOQL. This now implements the vast majority of querying capabilities required with one … Continue reading

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DataNucleus started out as JPOX, which started as TJDO. This had support for RDBMS, and in particular JDOQL querying. Unfortunately the TJDO process for JDOQL was a sequential parse of the query string, generating the SQL for the query. While … Continue reading

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JDO 2.3 Metadata API

Defining how classes are to be persisted has always been a subjective part of any persistence process. Some people like XML, some like annotations, and some want it all to be done magically with a sprinkle of stardust. JDO has … Continue reading

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