This section will be a brief introduction to JDBC, addressing the basics of JDBC, issues, caveats, and so forth. For
more detailed information, visit the JDBC website (
https://java.sun.com/products/jdbc/
), which
has many good resources and will always provide the most up to date information. Also, the API documentation included with
your JDK has detailed information on specific classes, methods, and fields. Look for the
java.sql package.
JDBC has classes to represent most of the basic pieces of a program's interaction with SQL. The classes are:
Connection, Statement,
ResultSet, Blob, and Clob,
and they all map directly to some concept in SQL. JDBC also has helper classes, such as
ResultSetMetaData and DatabaseMetaData, that represent
meta-information. These are useful for when you'd like to get information about the capabilities of the database. They are
also useful for getting the types of results returned by a query, either for debugging, or because you don't know about the
data you are dealing with.
PostgreSQL's JDBC interface also provides classes to map to PostgreSQL's non-standard extensions to JDBC's SQL support.
These non-standard extensions include: Fastpath, geometric types, native large objects, and
a class that aids serialization of Java objects into the database.