DataNucleus Access Platform v2.2.2發佈 符合標準的JAVA持久化引擎

DataNucleus Access Platform是一個符合標準的JAVA持久化引擎。 它完全符合JDO1，JDO2，JDO2.1與JPA1 JAVA標準。 此外它還遵循OGC簡單要素規範（Simple Feature HTTP://www.aliyun.com/zixun/aggregation/29909.html"> Specification）用於地理空間資料類型的持久化。 DataNucleus支援當前所有流行RDBMS和db4o，LDAP，Excel檔，XML資料庫。

DataNucleus Access Platform 2.2.2 ("Geiger") is released. DataNucleus Access Platform provides persistence and retrieval of JAVA objects to/from a wide range of datastores includin g RDBMS, db4o, LDAP, XML, and Excel. Version 2.2.2 includes the following changes over 2.2.1

· Add support for associated value mechanism for 1-N maps to reduce the number of SQL statements used (been supported for 1- N lists/sets for 2 yrs)
· Bug fix to metadata handling for embedded fields, when embedded field definition not provided
· JPA : Bug fix to query compilation of JPQL "NOT IN (subquery)"
· JPA : Support for @MapKeyEnumerated to define the type of column
· JPA : Bug fix to processing of <column> within unique-constraint in XML metadata
· JPA : Support for multiple inherited @MappedSuperclass
· RDBMS : Bug fix to race condition in statement batching (Gerd Behrmann)
· RDBMS : Support for use of "count()" size method when range specified on query
· RDBMS : Fix to Derby 10.6 change in handling of boolean/integer comparisons
· RDBMS : Bug fix to Postgresql handling of index generation, now omitting the schema name
· Other minor cleanups