Java Database Connectivity

2. JDBC :- is used for accessing databases from
Java applications
A Java API for executing SQL statements
• Extends the Java language.
• Supported by the java.sql package
• uniform interface to different data sources so
programmer writes ONE database interface; using
JDBC, program can access any data
source without recoding

4.  Open Database Connectivity developed by Microsoft
to provide interaction with databases using SQL.
 Use the JDBC-ODBC bridge to make ODBC work with
Java.
Since it's going to take some time for vendors to create
JDBC drivers, Javasoft has released a JDBC-ODBC
bridge that allows you to create Java applications to
talk to ODBC drivers which are readily available today

6. 6
JDBC Architecture (cont.)
Application JDBC Driver
• Java code calls JDBC library
• JDBC loads a driver
• Driver talks to a particular database
• An application can work with several databases by
using all corresponding drivers

7. 7
• Load the driver
• Define the connection URL
• Establish the connection
• Create a Statement object
• Execute a query using the Statement

8. Driver Manager - loads the database drivers, and manages
the connection between the application and the driver.
Driver - translates API calls into operations for a specific data
source.
Connection - A session between an application and a
database.
Statement - An SQL statement to perform.
PreparedStatement - a precompiled and stored query.
ResultSet - logical set of data returned by executing a
statement.
MetaData - Information about the returned data (resultset)
including the attribute names and types.

9. Class.forName("oracle.jdbc.OracleDriver");
Load a Given Class Name in Main Memory

10.  Connection cn;
 DriverManager.getConnection(URL, user, pwd);
cn=DriverManager.getConnection("jdbc:oracle:thin:@loca
lhost:1521:SHIKO", "bank", "bank");

11.  We use Statement objects in order to
 Query the database
 Update the database
 They are created by the Connection
Statement st=cn.createStatement();

12. rs pointer pointing to the before first
rs=st.executeQuery("Select * from Categories");

15. C . R . U . D
Up Date

17. JDBC Reference
ResultSet
- Provides access to records resulting from a query.
METHODS:
public void afterLast () throws SQLException
- moves the cursor to the end of the result set.
public void beforeFirst () throws SQLException
- moves the cursor to the beginning of the resultset.
public void cancelRowUpdates () throws SQLException
- cancels any updates made to this row.
public void close() throws SQLException
- closes the resultset.
public void deleteRow () throws SQLException
- deletes the current row from the resultset and the database.
public void first () throws SQLException
- moves the cursor to the first row of the resultset.
public void last () throws SQLException
- moves the cursor to the last row of the resultset.

18. JDBC Reference
ResultSet
METHODS:
public boolean getBoolean (String cname) throws SQLException
- returns the value of the named column(cname) in Boolean format.
public Date getDate (String cname) throws SQLException
- returns the value of the named column(cname) in Date format.
public double getDouble (String cname) throws SQLException
- returns the value of the named column(cname) in Double format.
public float getFloat (String cname) throws SQLException
- returns the value of the named column(cname) in Float format.
public int getInt (String cname) throws SQLException
- returns the value of the named column(cname) in Int format.
public String getString (String cname) throws SQLException
- returns the value of the named column(cname) in String format.
public ResultSetMetaData getMetaData ( ) throws SQLException
- returns the meta-data object for this resultset.
public void insertRow ( ) throws SQLException
- inserts the contents of the insert row into the result set and database.