A.2 Overview of JDBC 2.0 Core API Changes

The JDBC 2.0 core API includes the JDBC 1.0 API and adds enhancements and new functionality to it. These additions put the Java programming language at the forefront of database computing, providing both universal data access and improved performance.
Applications that use earlier versions of the JDBC API can be run using the Java 2 platform with no problem, in keeping with the goal of backward compatibility. However, an application that takes advantage of the new 2.0 features must be run with a driver that implements those features.

The new features in the JDBC 2.0 core API fall into two broad categories: support for new functionality and support for the SQL99 data types.

16. Support for new functionality

• scrollable result sets
• batch updates
• programmatic inserts, deletes, and updates
• other

• performance hints
• character streams for streams of internationalized Unicode characters
• full precision for java.math.BigDecimal values
• support for time zones in Date, Time, and Timestamp values


17. Support for advanced data types

• new SQL data types (SQL99 types)
• increased support for storing persistent objects in the Java programming language

In addition to making the retrieval, storage, and manipulation of data more convenient, the new features make JDBC applications more efficient. For example, batch updates can increase performance dramatically. The new interfaces Blob, Clob, and Array allow applications to operate on large amounts of data without having to materialize the data on the client, which can mean a significant savings in transfer time and the amount of memory needed. Also, new methods for setting the fetch size and fetch direction let a programmer fine tune an application for more efficient data retrieval and processing.