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 Provides the API for accessing and processing data stored in a
 data source (usually a relational database) using the
 Java<sup><font size=-2>TM</font></sup> programming language.
 This API includes a framework whereby different
 drivers can be installed dynamically to access different data sources.
 Although the JDBC<sup><font size=-2>TM</font></sup> API is mainly geared
 to passing SQL statements to a database, it provides for reading and
 writing data from any data source with a tabular format.
 The reader/writer facility, available through the
 <code>javax.sql.RowSet</code> group of interfaces, can be customized to
 use and update data from a spread sheet, flat file, or any other tabular
 data source.
 <P>
 <h2>What the JDBC<sup><font size=-2>TM</font></sup> 4.1 API Includes</h2>
 The JDBC<sup><font size=-2>TM</font></sup> 4.1 API includes both
 the <code>java.sql</code> package, referred to as the JDBC core API,
 and the <code>javax.sql</code> package, referred to as the JDBC Optional
 Package API. This complete JDBC API
 is included in the Java<sup><font size=-2>TM</font></sup>
 Standard Edition (Java SE<sup><font size=-2>TM</font></sup>), version 7.
 The <code>javax.sql</code> package extends the functionality of the JDBC API
 from a client-side API to a server-side API, and it is an essential part
 of the Java<sup><font size=-2>TM</font></sup>  Enterprise Edition
 (Java EE<sup><font size=-2>TM</font></sup>) technology.
 <P>
 <h2>Versions</h2>
 The JDBC 4.1 API incorporates all of the previous JDBC API versions:
 <UL>
  <LI> The JDBC 4.0 API
  <LI> The JDBC 3.0 API
  <LI> The JDBC 2.1 core API
  <LI> The JDBC 2.0 Optional Package API<br>
       (Note that the JDBC 2.1 core API and the JDBC 2.0 Optional Package
       API together are referred to as the JDBC 2.0 API.)
  <LI> The JDBC 1.2 API
  <LI> The JDBC 1.0 API
 </UL>
 <P>
 Classes, interfaces, methods, fields, constructors, and exceptions
 have the following "since" tags that indicate when they were introduced
 into the Java platform. When these "since" tags are used in
 Javadoc<sup><font size=-2>TM</font></sup> comments for the JDBC API,
 they indicate the following:
 <UL>
  <LI>Since 1.7 -- new in the JDBC 4.1 API and part of the Java SE platform,
      version 7
 <LI>Since 1.6 -- new in the JDBC 4.0 API and part of the Java SE platform,
      version 6
  <LI>Since 1.4 -- new in the JDBC 3.0 API and part of the J2SE platform,
      version 1.4
  <LI>Since 1.2 -- new in the JDBC 2.0 API and part of the J2SE platform,
      version 1.2
  <LI>Since 1.1 or no "since" tag -- in the original JDBC 1.0 API and part of
       the JDK<sup><font size=-2>TM</font></sup>, version 1.1
 </UL>
 <P>
 <b>NOTE:</b> Many of the new features are optional; consequently, there is
 some variation in drivers and the features they support. Always
 check your driver's documentation to see whether it supports a feature before
 you try to use it.
 <P>
 <b>NOTE:</b> The class <code>SQLPermission</code> was added in the
 Java<sup><font size=-2>TM</font></sup> 2 SDK, Standard Edition,
 version 1.3 release. This class is used to prevent unauthorized
 access to the logging stream associated with the <code>DriverManager</code>,
 which may contain information such as table names, column data, and so on.
 <p>

 <h2>What the <code>java.sql</code> Package Contains</h2>
 The <code>java.sql</code> package contains API for the following:
 <UL>
   <LI>Making a connection with a database via the <code>DriverManager</code> facility
   <UL>
 	 <LI><code>DriverManager</code> class -- makes a connection with a driver
 	 <LI><code>SQLPermission</code> class -- provides permission when code
                   running within a Security Manager, such as an applet,
                   attempts to set up a logging stream through the
                   <code>DriverManager</code>
 	 <LI><code>Driver</code> interface -- provides the API for registering
              and connecting drivers based on JDBC technology ("JDBC drivers");
              generally used only by the <code>DriverManager</code> class
 	 <LI><code>DriverPropertyInfo</code> class -- provides properties for a
              JDBC driver; not used by the general user
   </UL>
   <LI>Sending SQL statements to a database
   <UL>
 	 <LI><code>Statement</code> --  used to send basic SQL statements
 	 <LI><code>PreparedStatement</code> --  used to send prepared statements or
               basic SQL statements (derived from <code>Statement</code>)
 	 <LI><code>CallableStatement</code> --  used to call database stored
               procedures (derived from <code>PreparedStatement</code>)
 	 <LI><code>Connection</code> interface --  provides methods for creating
              statements and managing connections and their properties
 	 <LI><code>Savepoint</code> --  provides savepoints in a transaction

   </UL>
   <LI>Retrieving and updating the results of a query
   <UL>
 	 <LI><code>ResultSet</code> interface
   </UL>
   <LI>Standard mappings for SQL types to classes and interfaces in the
       Java programming language
   <UL>
 	 <LI><code>Array</code> interface -- mapping for SQL <code>ARRAY</code>
 	 <LI><code>Blob</code> interface -- mapping for SQL <code>BLOB</code>
 	 <LI><code>Clob</code> interface -- mapping for SQL <code>CLOB</code>
 	 <LI><code>Date</code> class -- mapping for SQL <code>DATE</code>
 	  <LI><code>NClob</code> interface -- mapping for SQL <code>NCLOB</code>
 	 <LI><code>Ref</code> interface -- mapping for SQL <code>REF</code>
 	  <LI><code>RowId</code> interface -- mapping for SQL <code>ROWID</code>
 	 <LI><code>Struct</code> interface -- mapping for SQL <code>STRUCT</code>
 	  <LI><code>SQLXML</code> interface -- mapping for SQL <code>XML</code>
 	 <LI><code>Time</code> class -- mapping for SQL <code>TIME</code>
 	 <LI><code>Timestamp</code> class -- mapping for SQL <code>TIMESTAMP</code>
 	 <LI><code>Types</code> class -- provides constants for SQL types
   </UL>
   <LI>Custom mapping an SQL user-defined type (UDT) to a class in the
 	  Java programming language
   <UL>
 	 <LI><code>SQLData</code> interface -- specifies the mapping of
               a UDT to an instance of this class
 	 <LI><code>SQLInput</code> interface -- provides methods for reading
               UDT attributes from a stream
 	 <LI><code>SQLOutput</code> interface -- provides methods for writing
               UDT attributes back to a stream
   </UL>
   <LI>Metadata
   <UL>
 	 <LI><code>DatabaseMetaData</code> interface -- provides information
               about the database
 	 <LI><code>ResultSetMetaData</code> interface -- provides information
               about the columns of a <code>ResultSet</code> object
 	 <LI><code>ParameterMetaData</code> interface -- provides information
               about the parameters to <code>PreparedStatement</code> commands
   </UL>
   <LI>Exceptions
 	<UL>
 	  <LI><code>SQLException</code> -- thrown by most methods when there
 		 is a problem accessing data and by some methods for other reasons
 	  <LI><code>SQLWarning</code> -- thrown to indicate a warning
 	  <LI><code>DataTruncation</code> -- thrown to indicate that data may have
      	  been truncated
 	  <LI><code>BatchUpdateException</code> -- thrown to indicate that not all
 		 commands in a batch update executed successfully
 	</UL>
 </UL>
 <P>
     <h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 4.1 API</h3>
 <UL>
     <LI>Allow <code>Connection</code>,
         <code>ResultSet</code> and <code>Statement</code> objects to be
         used with the try-with-resources statement</LI>
     <LI>Supported added to <code>CallableStatement</code> and
         <code>ResultSet</code> to specify the Java type to convert to via the
         <code>getObject</code> method</LI>
     <LI><code>DatabaseMetaData</code> methods to return PseudoColumns and if a
         generated key is always returned</LI>
     <LI>Added support to <code>Connection</code> to specify a database schema,
     abort and timeout a physical connection.</LI>
     <LI>Added support to close a <code>Statement</code> object when its dependent
     objects have been closed</LI>
     <LI>Support for obtaining the parent logger for a <code>Driver</code>,
      <code>DataSource</code>, <code>ConnectionPoolDataSource</code> and
      <code>XADataSource</code></LI>

 </UL>
 <h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 4.0 API</h3>
 <UL>
   <LI>auto java.sql.Driver discovery -- no longer need to load a
 <code>java.sql.Driver</code> class via <code>Class.forName</code>
  <LI>National Character Set support added
  <li>Support added for the SQL:2003 XML data type
  <lI>SQLException enhancements -- Added support for cause chaining; New SQLExceptions
  added for common SQLState class value codes
  <li>Enhanced Blob/Clob functionality -- Support provided to create and free a Blob/Clob instance
  as well as additional methods added to improve accessiblity
  <li>Support added for accessing a SQL ROWID
  <li>Support added to allow a JDBC application to access an instance of a JDBC resource
  that has been wrapped by a vendor, usually in an application server or connection
  pooling environment.
  <li>Availability to be notified when a <code>PreparedStatement</code> that is associated
  with a <code>PooledConnection</code> has been closed or the driver determines is invalid


 </UL>
 <P>
 <P>
 <h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 3.0 API</h3>
 <UL>
   <LI>Pooled statements -- reuse of statements associated with a pooled
        connection
   <LI>Savepoints -- allow a transaction to be rolled back to a designated
       savepoint
   <LI>Properties defined for <code>ConnectionPoolDataSource</code> -- specify
       how connections are to be pooled
   <LI>Metadata for parameters of a <code>PreparedStatement</code> object
   <LI>Ability to retrieve values from automatically generated columns
   <LI>Ability to have multiple <code>ResultSet</code> objects
        returned from <code>CallableStatement</code> objects open at the
       same time
   <LI>Ability to identify parameters to <code>CallableStatement</code>
       objects by name as well as by index
   <LI><code>ResultSet</code> holdability -- ability to specify whether cursors
       should be held open or closed at the end of a transaction
   <LI>Ability to retrieve and update the SQL structured type instance that a
       <code>Ref</code> object references
   <LI>Ability to programmatically update <code>BLOB</code>,
       <code>CLOB</code>, <code>ARRAY</code>, and <code>REF</code> values.
   <LI>Addition of the <code>java.sql.Types.DATALINK</code> data type --
       allows JDBC drivers access to objects stored outside a data source
   <LI>Addition of metadata for retrieving SQL type hierarchies
 </UL>
 <P>
 <h3><code>java.sql</code> Features Introduced in the JDBC 2.1 Core API</h3>
 <UL>
   <LI>Scrollable result sets--using new methods in the <code>ResultSet</code>
 	  interface that allow the cursor to be moved to a particular row or to a
 	  position relative to its current position
   <LI>Batch updates
   <LI>Programmatic updates--using <code>ResultSet</code> updater methods
   <LI>New data types--interfaces mapping the SQL3 data types
   <LI>Custom mapping of user-defined types (UDTs)
   <LI>Miscellaneous features, including performance hints, the use of character
 	  streams, full precision for <code>java.math.BigDecimal</code> values,
 	  additional security, and
 	  support for time zones in date, time, and timestamp values.
 </UL>
 <P>
 <h3><code>javax.sql</code> Features Introduced in the JDBC 2.0 Optional
 Package API</h3>
 <UL>
   <LI>The <code>DataSource</code> interface as a means of making a connection.  The
       Java Naming and Directory Interface<sup><font size=-2>TM</font></sup>
       (JNDI) is used for registering a <code>DataSource</code> object with a
       naming service and also for  retrieving it.
   <LI>Pooled connections -- allowing connections to be used and reused
   <LI>Distributed transactions -- allowing a transaction to span diverse
       DBMS servers
   <LI><code>RowSet</code> technology -- providing a convenient means of
        handling and passing data
 </UL>
 <P>
 <P>
 <h3>Custom Mapping of UDTs</h3>
 A user-defined type (UDT) defined in SQL can be mapped to a class in the Java
 programming language. An SQL structured type or an SQL <code>DISTINCT</code>
 type are the UDTs that may be custom mapped.  The following three
 steps set up a custom mapping:
 <ol>
   <li>Defining the SQL structured type or <code>DISTINCT</code> type in SQL
   <li>Defining the class in the Java programming language to which the
 	  SQL UDT will be mapped.  This class must implement the
 	  <code>SQLData</code> interface.
   <li>Making an entry in a <code>Connection</code> object's type map
       that contains two things:
    <ul>
        <li>the fully-qualified SQL name of the UDT
        <li>the <code>Class</code> object for the class that implements the
            <code>SQLData</code> interface
    </ul>
 </ol>
 <p>
 When these are in place for a UDT, calling the methods
 <code>ResultSet.getObject</code> or <code>CallableStatement.getObject</code>
 on that UDT will automatically retrieve the custom mapping for it. Also, the
 <code>PreparedStatement.setObject</code> method will automatically map the
 object back to its SQL type to store it in the data source.

 <h2>Package Specification</h2>

 <ul>
   <li><a href="http://java.sun.com/products/jdbc/download.html">Specification
       of the JDBC 4.0 API</a>
 </ul>

 <h2>Related Documentation</h2>

 <ul>
   <li><a href="../../../technotes/guides/jdbc/getstart/GettingStartedTOC.fm.html">Getting Started</a>--overviews of the major interfaces
 <P>
   <li><a href="http://java.sun.com/docs/books/tutorial/jdbc">Chapters on the JDBC
      API</a>--from the online version of <i>The Java Tutorial Continued</i>
 <P>
   <li><a href="http://java.sun.com/docs/books/jdbc">
 <i>JDBC<sup><font size=-2>TM</font></sup>API Tutorial and Reference,
 Third Edition</i></a>--
 a complete reference and tutorial for the JDBC 3.0 API
 </ul>
 <P>
 @since 1.1
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	This code is distributed in the hope that it will be useful, but WITHOUT
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	FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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	accompanied this code).

	You should have received a copy of the GNU General Public License version
	2 along with this work; if not, write to the Free Software Foundation,
	Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

	Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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	<body bgcolor="white">

	Provides the API for accessing and processing data stored in a
	data source (usually a relational database) using the
	Java<sup><font size=-2>TM</font></sup> programming language.
	This API includes a framework whereby different
	drivers can be installed dynamically to access different data sources.
	Although the JDBC<sup><font size=-2>TM</font></sup> API is mainly geared
	to passing SQL statements to a database, it provides for reading and
	writing data from any data source with a tabular format.
	The reader/writer facility, available through the
	<code>javax.sql.RowSet</code> group of interfaces, can be customized to
	use and update data from a spread sheet, flat file, or any other tabular
	data source.
	<P>
	<h2>What the JDBC<sup><font size=-2>TM</font></sup> 4.1 API Includes</h2>
	The JDBC<sup><font size=-2>TM</font></sup> 4.1 API includes both
	the <code>java.sql</code> package, referred to as the JDBC core API,
	and the <code>javax.sql</code> package, referred to as the JDBC Optional
	Package API. This complete JDBC API
	is included in the Java<sup><font size=-2>TM</font></sup>
	Standard Edition (Java SE<sup><font size=-2>TM</font></sup>), version 7.
	The <code>javax.sql</code> package extends the functionality of the JDBC API
	from a client-side API to a server-side API, and it is an essential part
	of the Java<sup><font size=-2>TM</font></sup> Enterprise Edition
	(Java EE<sup><font size=-2>TM</font></sup>) technology.
	<P>
	<h2>Versions</h2>
	The JDBC 4.1 API incorporates all of the previous JDBC API versions:
	<UL>
	<LI> The JDBC 4.0 API
	<LI> The JDBC 3.0 API
	<LI> The JDBC 2.1 core API
	<LI> The JDBC 2.0 Optional Package API<br>
	(Note that the JDBC 2.1 core API and the JDBC 2.0 Optional Package
	API together are referred to as the JDBC 2.0 API.)
	<LI> The JDBC 1.2 API
	<LI> The JDBC 1.0 API
	</UL>
	<P>
	Classes, interfaces, methods, fields, constructors, and exceptions
	have the following "since" tags that indicate when they were introduced
	into the Java platform. When these "since" tags are used in
	Javadoc<sup><font size=-2>TM</font></sup> comments for the JDBC API,
	they indicate the following:
	<UL>
	<LI>Since 1.7 -- new in the JDBC 4.1 API and part of the Java SE platform,
	version 7
	<LI>Since 1.6 -- new in the JDBC 4.0 API and part of the Java SE platform,
	version 6
	<LI>Since 1.4 -- new in the JDBC 3.0 API and part of the J2SE platform,
	version 1.4
	<LI>Since 1.2 -- new in the JDBC 2.0 API and part of the J2SE platform,
	version 1.2
	<LI>Since 1.1 or no "since" tag -- in the original JDBC 1.0 API and part of
	the JDK<sup><font size=-2>TM</font></sup>, version 1.1
	</UL>
	<P>
	<b>NOTE:</b> Many of the new features are optional; consequently, there is
	some variation in drivers and the features they support. Always
	check your driver's documentation to see whether it supports a feature before
	you try to use it.
	<P>
	<b>NOTE:</b> The class <code>SQLPermission</code> was added in the
	Java<sup><font size=-2>TM</font></sup> 2 SDK, Standard Edition,
	version 1.3 release. This class is used to prevent unauthorized
	access to the logging stream associated with the <code>DriverManager</code>,
	which may contain information such as table names, column data, and so on.
	<p>

	<h2>What the <code>java.sql</code> Package Contains</h2>
	The <code>java.sql</code> package contains API for the following:
	<UL>
	<LI>Making a connection with a database via the <code>DriverManager</code> facility
	<UL>
	<LI><code>DriverManager</code> class -- makes a connection with a driver
	<LI><code>SQLPermission</code> class -- provides permission when code
	running within a Security Manager, such as an applet,
	attempts to set up a logging stream through the
	<code>DriverManager</code>
	<LI><code>Driver</code> interface -- provides the API for registering
	and connecting drivers based on JDBC technology ("JDBC drivers");
	generally used only by the <code>DriverManager</code> class
	<LI><code>DriverPropertyInfo</code> class -- provides properties for a
	JDBC driver; not used by the general user
	</UL>
	<LI>Sending SQL statements to a database
	<UL>
	<LI><code>Statement</code> -- used to send basic SQL statements
	<LI><code>PreparedStatement</code> -- used to send prepared statements or
	basic SQL statements (derived from <code>Statement</code>)
	<LI><code>CallableStatement</code> -- used to call database stored
	procedures (derived from <code>PreparedStatement</code>)
	<LI><code>Connection</code> interface -- provides methods for creating
	statements and managing connections and their properties
	<LI><code>Savepoint</code> -- provides savepoints in a transaction

	</UL>
	<LI>Retrieving and updating the results of a query
	<UL>
	<LI><code>ResultSet</code> interface
	</UL>
	<LI>Standard mappings for SQL types to classes and interfaces in the
	Java programming language
	<UL>
	<LI><code>Array</code> interface -- mapping for SQL <code>ARRAY</code>
	<LI><code>Blob</code> interface -- mapping for SQL <code>BLOB</code>
	<LI><code>Clob</code> interface -- mapping for SQL <code>CLOB</code>
	<LI><code>Date</code> class -- mapping for SQL <code>DATE</code>
	<LI><code>NClob</code> interface -- mapping for SQL <code>NCLOB</code>
	<LI><code>Ref</code> interface -- mapping for SQL <code>REF</code>
	<LI><code>RowId</code> interface -- mapping for SQL <code>ROWID</code>
	<LI><code>Struct</code> interface -- mapping for SQL <code>STRUCT</code>
	<LI><code>SQLXML</code> interface -- mapping for SQL <code>XML</code>
	<LI><code>Time</code> class -- mapping for SQL <code>TIME</code>
	<LI><code>Timestamp</code> class -- mapping for SQL <code>TIMESTAMP</code>
	<LI><code>Types</code> class -- provides constants for SQL types
	</UL>
	<LI>Custom mapping an SQL user-defined type (UDT) to a class in the
	Java programming language
	<UL>
	<LI><code>SQLData</code> interface -- specifies the mapping of
	a UDT to an instance of this class
	<LI><code>SQLInput</code> interface -- provides methods for reading
	UDT attributes from a stream
	<LI><code>SQLOutput</code> interface -- provides methods for writing
	UDT attributes back to a stream
	</UL>
	<LI>Metadata
	<UL>
	<LI><code>DatabaseMetaData</code> interface -- provides information
	about the database
	<LI><code>ResultSetMetaData</code> interface -- provides information
	about the columns of a <code>ResultSet</code> object
	<LI><code>ParameterMetaData</code> interface -- provides information
	about the parameters to <code>PreparedStatement</code> commands
	</UL>
	<LI>Exceptions
	<UL>
	<LI><code>SQLException</code> -- thrown by most methods when there
	is a problem accessing data and by some methods for other reasons
	<LI><code>SQLWarning</code> -- thrown to indicate a warning
	<LI><code>DataTruncation</code> -- thrown to indicate that data may have
	been truncated
	<LI><code>BatchUpdateException</code> -- thrown to indicate that not all
	commands in a batch update executed successfully
	</UL>
	</UL>
	<P>
	<h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 4.1 API</h3>
	<UL>
	<LI>Allow <code>Connection</code>,
	<code>ResultSet</code> and <code>Statement</code> objects to be
	used with the try-with-resources statement</LI>
	<LI>Supported added to <code>CallableStatement</code> and
	<code>ResultSet</code> to specify the Java type to convert to via the
	<code>getObject</code> method</LI>
	<LI><code>DatabaseMetaData</code> methods to return PseudoColumns and if a
	generated key is always returned</LI>
	<LI>Added support to <code>Connection</code> to specify a database schema,
	abort and timeout a physical connection.</LI>
	<LI>Added support to close a <code>Statement</code> object when its dependent
	objects have been closed</LI>
	<LI>Support for obtaining the parent logger for a <code>Driver</code>,
	<code>DataSource</code>, <code>ConnectionPoolDataSource</code> and
	<code>XADataSource</code></LI>

	</UL>
	<h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 4.0 API</h3>
	<UL>
	<LI>auto java.sql.Driver discovery -- no longer need to load a
	<code>java.sql.Driver</code> class via <code>Class.forName</code>
	<LI>National Character Set support added
	<li>Support added for the SQL:2003 XML data type
	<lI>SQLException enhancements -- Added support for cause chaining; New SQLExceptions
	added for common SQLState class value codes
	<li>Enhanced Blob/Clob functionality -- Support provided to create and free a Blob/Clob instance
	as well as additional methods added to improve accessiblity
	<li>Support added for accessing a SQL ROWID
	<li>Support added to allow a JDBC application to access an instance of a JDBC resource
	that has been wrapped by a vendor, usually in an application server or connection
	pooling environment.
	<li>Availability to be notified when a <code>PreparedStatement</code> that is associated
	with a <code>PooledConnection</code> has been closed or the driver determines is invalid


	</UL>
	<P>
	<P>
	<h3><code>java.sql</code> and <code>javax.sql</code> Features Introduced in the JDBC 3.0 API</h3>
	<UL>
	<LI>Pooled statements -- reuse of statements associated with a pooled
	connection
	<LI>Savepoints -- allow a transaction to be rolled back to a designated
	savepoint
	<LI>Properties defined for <code>ConnectionPoolDataSource</code> -- specify
	how connections are to be pooled
	<LI>Metadata for parameters of a <code>PreparedStatement</code> object
	<LI>Ability to retrieve values from automatically generated columns
	<LI>Ability to have multiple <code>ResultSet</code> objects
	returned from <code>CallableStatement</code> objects open at the
	same time
	<LI>Ability to identify parameters to <code>CallableStatement</code>
	objects by name as well as by index
	<LI><code>ResultSet</code> holdability -- ability to specify whether cursors
	should be held open or closed at the end of a transaction
	<LI>Ability to retrieve and update the SQL structured type instance that a
	<code>Ref</code> object references
	<LI>Ability to programmatically update <code>BLOB</code>,
	<code>CLOB</code>, <code>ARRAY</code>, and <code>REF</code> values.
	<LI>Addition of the <code>java.sql.Types.DATALINK</code> data type --
	allows JDBC drivers access to objects stored outside a data source
	<LI>Addition of metadata for retrieving SQL type hierarchies
	</UL>
	<P>
	<h3><code>java.sql</code> Features Introduced in the JDBC 2.1 Core API</h3>
	<UL>
	<LI>Scrollable result sets--using new methods in the <code>ResultSet</code>
	interface that allow the cursor to be moved to a particular row or to a
	position relative to its current position
	<LI>Batch updates
	<LI>Programmatic updates--using <code>ResultSet</code> updater methods
	<LI>New data types--interfaces mapping the SQL3 data types
	<LI>Custom mapping of user-defined types (UDTs)
	<LI>Miscellaneous features, including performance hints, the use of character
	streams, full precision for <code>java.math.BigDecimal</code> values,
	additional security, and
	support for time zones in date, time, and timestamp values.
	</UL>
	<P>
	<h3><code>javax.sql</code> Features Introduced in the JDBC 2.0 Optional
	Package API</h3>
	<UL>
	<LI>The <code>DataSource</code> interface as a means of making a connection. The
	Java Naming and Directory Interface<sup><font size=-2>TM</font></sup>
	(JNDI) is used for registering a <code>DataSource</code> object with a
	naming service and also for retrieving it.
	<LI>Pooled connections -- allowing connections to be used and reused
	<LI>Distributed transactions -- allowing a transaction to span diverse
	DBMS servers
	<LI><code>RowSet</code> technology -- providing a convenient means of
	handling and passing data
	</UL>
	<P>
	<P>
	<h3>Custom Mapping of UDTs</h3>
	A user-defined type (UDT) defined in SQL can be mapped to a class in the Java
	programming language. An SQL structured type or an SQL <code>DISTINCT</code>
	type are the UDTs that may be custom mapped. The following three
	steps set up a custom mapping:
	<ol>
	<li>Defining the SQL structured type or <code>DISTINCT</code> type in SQL
	<li>Defining the class in the Java programming language to which the
	SQL UDT will be mapped. This class must implement the
	<code>SQLData</code> interface.
	<li>Making an entry in a <code>Connection</code> object's type map
	that contains two things:
	<ul>
	<li>the fully-qualified SQL name of the UDT
	<li>the <code>Class</code> object for the class that implements the
	<code>SQLData</code> interface
	</ul>
	</ol>
	<p>
	When these are in place for a UDT, calling the methods
	<code>ResultSet.getObject</code> or <code>CallableStatement.getObject</code>
	on that UDT will automatically retrieve the custom mapping for it. Also, the
	<code>PreparedStatement.setObject</code> method will automatically map the
	object back to its SQL type to store it in the data source.

	<h2>Package Specification</h2>

	<ul>
	<li><a href="http://java.sun.com/products/jdbc/download.html">Specification
	of the JDBC 4.0 API</a>
	</ul>

	<h2>Related Documentation</h2>

	<ul>
	<li><a href="../../../technotes/guides/jdbc/getstart/GettingStartedTOC.fm.html">Getting Started</a>--overviews of the major interfaces
	<P>
	<li><a href="http://java.sun.com/docs/books/tutorial/jdbc">Chapters on the JDBC
	API</a>--from the online version of <i>The Java Tutorial Continued</i>
	<P>
	<li><a href="http://java.sun.com/docs/books/jdbc">
	<i>JDBC<sup><font size=-2>TM</font></sup>API Tutorial and Reference,
	Third Edition</i></a>--
	a complete reference and tutorial for the JDBC 3.0 API
	</ul>
	<P>
	@since 1.1
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