JDBC Versions

1). The JDBC 1.0 API.
2). The JDBC 1.2 API.
3). The JDBC 2.0 Optional Package API.
4). The JDBC 2.1 core API.
5) The JDBC 3.0 API.
6) The JDBC 4.0 API.
Features of JDBC 1.0 API
The JDBC 1.0 API was the first officially JDBC API launched consists of the following java classes and interfaces that you can open connections to particular databases.
This version includes a completely redesigned administration console with an enhanced graphical interface to manage and monitor distributed virtual databases.
Features of JDBC 1.2 API
1). It supports Updatabale ResultSets.
2). The DatabaseMetaData code has been refactored to provide more transparency with regard to the underlying database engine.
3) New pass through schedulers for increased performance.

Features of The JDBC 2.0 Optional Pacakage API
1). The use of DataSource interface for making a connection.
2). Use of JNDI to specify and obtain database connections.
3). It allows us to use Pooled connections, that is we can reuse the connections.
4). In this version the distrbuted transactions is possible.
5). It provides a way of handling and passing data using Rowset technology.
Features of the JDBC 2.1 core API.
1). Scroll forward and backward in a result set or has the ability to move to a specific row.
2). Instead of using SQL commands, we can make updates to a database tables using methods in the Java programming language
3). We can use multiple SQL statements in a a database as a unit, or batch.
4). It uses the SQL3 datatypes as column values. SQL3 types are Blob, Clob, Array, Structured type, Ref.
5). Increased support for storing persistent objects in the java programming language.
6). Supports for time zones in Date, Time, and Timestamp values.
7). Full precision for java.math.BigDecimal values.
Features of JDBC 3.0 API
1). Reusabilty of prepared statements by connection pools.
2). In this version there is number of properties defined for the ConnectionPoolDataSource. These properties can be used to describe how the PooledConnection objects created by DataSource objects should be pooled.
3) A new concept has been added to this API is of savepoints.
4). Retrieval of parameter metadata.
5). It has added a means of retrieving values from columns containing automatically generated values.
6). Added a new data type i.e. java.sql.BOOLEAN.
7). Passing parameters to CallableStatement.
8). The data in the Blob and Clob can be altered.
9). DatabaseMetaData API has been added.
Features of JDBC 4.0 :
1). Auto- loading of JDBC driver class.
2). Connection management enhancements.
3.) Support for RowId SAL type.
4). SQL exception handling enhancements.
5). DataSet implementation of SQl using Annotations.
6). SQL XML support
Features of JDBC 3.0 API
1. Reusabilty of prepared statements by connection pools.
2. In this version there is number of properties defined for the ConnectionPoolDataSource. These properties can be used to describe how the PooledConnection objects created by DataSource objects should be pooled.
3. A new concept has been added to this API is of savepoints: One of the useful new features is transactional savepoints. With JDBC 3.0, the transactional model is now more flexible. Now you can start a transaction , insert several rows in it and then create a savepoint. This savepoint serves as a bookmark. The application can rollback to the savepoint and then commit the group of inserts as if the updates have never been attempted. For eg:

Statement st=connection.createStatement();
int rowcount=st.executeUpdate("insert into employee values("tim"));
int rowcoutn=st.executeUpdate("insert into salary values(20000.0);
Savepoint sv=connection.setSavePoint("savepoint"); //create save point for inserts
int rowcount=st.executeUpdate("delete from employee");
connection.rollback(sv); //discard the delete statement but keeps the inserts
connection.commit(); //inserts are now permanent
4. Retrieval of parameter metadata.
5. It has added a means of retrieving values from columns containing automatically generated values.
6. Added a new data type i.e. java.sql.BOOLEAN.
7. Passing parameters to CallableStatement.
8. The data in the Blob and Clob can be altered: JDBC 3.0 introduces a standard mechanism for updating BLOB and CLOB data.
9. DatabaseMetaData API has been added.
10. It allows stored procedure parameters to be called by name.
Features of JDBC 4.0
JDBC 4 is a major new release with a strong focus ease-of-use and programmer productivity. JDBC 4's key priority is to make it easier for developers to work directly with the JDBC API. The new features availble in J2SE 1.5 added ease-of-development features in JDBC 4 In addition to ease-of-use, JDBC 4 introduces several SQL 203 features, like Java specific mapping for the new XML SQL type. Now in JDBC 4 every PreparedStatement is poolable by default.
1. Auto- loading of JDBC driver class: In JDBC 4 invoking the getConnection() on DriverManager will automatically load a driver. Upon loading the driver, an instance of the driver is created and the registerDriver() method is invoked to make that driver available to clients.
2. Connection management enhancements: In jdbc it may happen that a Connection is lying idle or not closed in a pool, then it became stale over time. This will led to the connection pool run out of resources due to stale connection. We know that the stale connection doesn't mean that a connection is closed. Now in JDBC 4 Connection class we have provided one method isValid(), which allows a client to query the database driver if a connection is still valid. As database is a shared resource, so many application can access the same data store. To maintain all the records of the client is a difficult task, now in JDBC 4 an application can associate metadata with a database connection via the setClientInfo() method, which takes a name/value pair, or a Properties object.
3. Support for RowId data type: JDBC introduces support for ROWID, a data type that had been in use in database products even before it became part of the SQL.
4. SQL exception handling enhancements: JDBC 4 addresses the error handling beautifully. As databases are often remotely accessible resources, problems such as network failures is common and it can cause exceptions when executing a database operation. SQL statements can also cause exceptions. Prior to JDBC 4, most JDBC operations generated a simple SQLException.
5. SQL XML support:

6. DataSet implementation of SQL using Annotations: The JDBC 4.0 specification leverages annotations to allow developers to associate a SQL query with a Java class without a need to write a lot of code to achieve this association.
Difference between JDBC 3.0 & JDBC 4.0
Features of JDBC 3.0
1. Reusabilty of prepared statements by connection pools.
2. In this version there is number of properties defined for the ConnectionPoolDataSource. These properties can be used to describe how the PooledConnection objects created by DataSource objects should be pooled.
3. A new concept has been added to this API is of savepoints: One of the useful new features is transactional savepoints. With JDBC 3.0, the transactional model is now more flexible. Now you can start a transaction , insert several rows in it and then create a savepoint. This savepoint serves as a bookmark. The application can rollback to the savepoint and then commit the group of inserts as if the updates have never been attempted. For eg:

Statement st=connection.createStatement();
int rowcount=st.executeUpdate("insert into employee values("tim"));
int rowcoutn=st.executeUpdate("insert into salary values(20000.0);
Savepoint sv=connection.setSavePoint("savepoint"); //create save point for inserts
int rowcount=st.executeUpdate("delete from employee");
connection.rollback(sv); //discard the delete statement but keeps the inserts
connection.commit(); //inserts are now permanent
4. Retrieval of parameter metadata.
5. It has added a means of retrieving values from columns containing automatically generated values.
6. Added a new data type i.e. java.sql.BOOLEAN.
7. Passing parameters to CallableStatement.
8. The data in the Blob and Clob can be altered: JDBC 3.0 introduces a standard mechanism for updating BLOB and CLOB data.
9. DatabaseMetaData API has been added.
10. It allows stored procedure parameters to be called by name.
Features of JDBC 4
JDBC 4 is a major new release with a strong focus ease-of-use and programmer productivity. JDBC 4's key priority is to make it easier for developers to work directly with the JDBC API. The new features availble in J2SE 1.5 added ease-of-development features in JDBC 4
In addition to ease-of-use, JDBC 4 introduces several SQL 203 features, like Java specific mapping for the new XML SQL type. Now in JDBC 4 every PreparedStatement is poolable by default.
1. Auto- loading of JDBC driver class: In JDBC 4 invoking the getConnection() on DriverManager will automatically load a driver. Upon loading the driver, an instance of the driver is created and the registerDriver() method is invoked to make that driver available to clients.
2. Connection management enhancements: In jdbc it may happen that a Connection is lying idle or not closed in a pool, then it became stale over time. This will led to the connection pool run out of resources due to stale connection. We know that the stale connection doesn't mean that a connection is closed. Now in JDBC 4 Connection class we have provided one method isValid(), which allows a client to query the database driver if a connection is still valid. As database is a shared resource, so many application can access the same data store. To maintain all the records of the client is a difficult task, now in JDBC 4 an application can associate metadata with a database connection via the setClientInfo() method, which takes a name/value pair, or a Properties object.
3. Support for RowId data type: JDBC introduces support for ROWID, a data type that had been in use in database products even before it became part of the SQL.
4. SQL exception handling enhancements: JDBC 4 addresses the error handling beautifully. As databases are often remotely accessible resources, problems such as network failures is common and it can cause exceptions when executing a database operation. SQL statements can also cause exceptions. Prior to JDBC 4, most JDBC operations generated a simple SQLException.
5. SQL XML support:
6. DataSet implementation of SQL using Annotations: The JDBC 4.0 specification leverages annotations to allow developers to associate a SQL query with a Java class without a need to write a lot of code to achieve this association.