Difference between revisions of "EclipseLink/Development/DBWS/OracleUseCases"

Revision as of 16:17, 17 December 2009

Supported Use-Cases for Oracle Platforms

All of the use-cases support for non-Oracle Platforms are supported on Oracle

The design-time utility DBWSBuilder uses custom Data Dictionary query for the Oracle Platform (the JDBC metadata API java.sql.DatabaseMetaData suffers from well-documented problems of accuracy and scope ¹). By doing so, additional use-cases can be supported:

• Advanced JDBC types
  • Object Types

java.sql.Struct's are realized in Oracle using proprietary types (oracle.sql.STRUCT) and APIs that are encapsulated in EclipseLink's DatabasePlatform (specifically org.eclipse.persistence.platform.database.oracle.Oracle8Platform or higher)

• • Array Types

java.sql.Array's are realized in Oracle using proprietary types (oracle.sql.VARRAY) and APIs that are encapsulated in EclipseLink's DatabasePlatform (specifically org.eclipse.persistence.platform.database.oracle.Oracle8Platform or higher)

• Advanced PL/SQL types
  • Record types
  • Collection types

¹ Compliance to the meta-data APIs available through the java.sql.DatabaseMetaData is weak - no vendor implements the APIs fully, nor in a standard fashion. For example, the simple act of getting the names of available databases is different across platforms: on Oracle the getSchemas method is used while for DB2/Sybase/MS SQLServer the getCatalogs method is used. Another example of cross-platform meta-data issues is the getColumns method: for PostgreSQL, the name of the table must be lower-case; for Oracle, it must be upper-case; others support mixed-case. link is a case-study of some of the issues.