A.1.1 Features Introduced in the JDBC 3.0 API

The JDBC 3.0 API introduces new material and changes in these areas:

• Savepoint support
Added the Savepoint interface, which contains new methods to set a savepoint, to release a savepoint, and to roll back a transaction to a designated savepoint.

• Reuse of prepared statements by connection pools
Added the ability for deployers to control how prepared statements are pooled and reused by connections.

• Connection pool configuration
Defined a number of properties for the ConnectionPoolDataSource interface. These properties can be used to describe how PooledConnection objects created by DataSource objects should be pooled.

• Retrieval of parameter metadata
Added the new interface ParameterMetaData, which describes the number, type, and properties of parameters to prepared statements.

• Retrieval of auto-generated keys
Added a means of retrieving values from columns containing automatically generated values.

• Ability to have multiple open ResultSet objects
Added the new method getMoreResults(int) that takes an argument that specifies whether ResultSet objects returned by a Statement should be closed before returning any subsequent ResultSet objects.

• Passing parameters to CallableStatement objects by name
Added methods to allow a string to identify the parameter to be set for a CallableStatement object.

• Holdable cursor support
Added the ability to specify whether a ResultSet object is kept open after a transaction has been committed.

• BOOLEAN data type
Added the data type java.sql.Types.BOOLEAN. BOOLEAN is logically equivalent to BIT.

• Making internal updates to the data in Blob and Clob objects
Added methods to allow the data contained in Blob and Clob objects to be altered.

• Retrieving and updating the object referenced by a Ref object
Added methods to retrieve the object referenced by a Ref object. Also added the ability to update a referenced object through the Ref object.

• Updating of columns containing BLOB, CLOB, ARRAY and REF types
Addition of the updateBlob, updateClob, updateArray, and updateRef methods to the ResultSet interface.

• DATALINK/URL data type
Added the data type java.sql.Types.DATALINK, allowing JDBC drivers to store and retrieve references to external data.

• Transform groups and type mapping
Described the effect of transform groups and how this is reflected in the metadata.

• Relationship between the JDBC SPI (Service Provider Interface) and the Connector architecture
Described the relationship between the JDBC SPI and the connector architecture.

• DatabaseMetadata APIs
Added metadata for retrieving SQL type hierarchies and various other kinds of information relating to new features.