Introduction to JDBC

(Java Database Connectivity)

Registering ODBC Data Source

Before using Java to access to MS Access DB, register the DB as an ODBC data source.

DB Registration Continued

To register Names.mdb as an ODBC data

source, use the following steps.

1. To open Data Sources (ODBC),

click Start,

click Control Panel, and then

click Administrative Tools.

Double-click Data Sources

(ODBC). 

2. Click Add

DB Registration Continued

3. Choose Microsoft Access

Driver.

4. Click Finish.

DB Registration Continued

5. Type the Data Source Name

6. Select the database to use.

Creating a Database

Step 1:Load the JDBC-ODBC bridge

Step 2:Connect to a data source

Step 3:Send SQL statements to create the

table. Step 4:

Use the table using SQL

1. JDBC-ODBC Bridge

Method 1Class.forName (“sun.jdbc.odbc.JdbcOdbcDriver”);

Method 2java -Djdbc.drivers

=sun.jdbc.odbc.JdbcOdbcDriver AProgram

2. Connect to a data source

JDBC data source (DB) is given in URL. URLs should be in the following form

jdbc:odbc:data-source-name Use DriverManager class, to connect to a URL DriverManager selects the appropriate driver

1. // database name = ClassList

2. String url = “jdbc:odbc:ClassList”;

3. String uname = “anonymous”;

4. String pword = “guest”;

5. Connection = DriverManager.getConnection(url,uname,pword);

3. Creating a Database

Ask for a Statement object Execute the SQL statement to create a table.

1. Statement stmt = con.createStatement();2. stmt.execute( "create table Names(“id integer” 3. + “fname varchar (32),“

+ “lname varchar(32));" );

In the above, create table Names( id integer, fname varchar

(32), lname varchar (20)); is a SQL statement.

4. Insert a Value

After you have created the table, you can the insert the appropriate values such as:

1. String st1 = “insert into Names values (1, ‘Angelia', ‘Jolie');”;

2. stmt.execute(st1);

4. Getting Information from a Database

Use executeQuery() method of a Statement object.

To store the return value of the query, use the ResultSet class.

1. ResultSet result = stmt.executeQuery( "SELECT * from Names;");

Class ResultSet 1

The general form of a result set is a table. It has

1. column headings

2. corresponding values Example

id fname lname

1 Angelina Jolie

2 Arnold Schwartz

Class ResultSet 2

Examine the ResultSet by: Moving to the first row of data.

result.next();

Extracting data from the columns of that row.

String fname = result.getString (“fname");

int cups = result.getInt (“id");

JDBC Exception Types

SQLException Basis of all JDBC exceptions

SQLWarning Noncritical error and is not thrown Extract this messages through the getWarnings

methods of Connection, ResultSet, and Statement

DataTruncation Special type of SQLWarning To detect, use instanceof DataTruncation check on

each SQLWarning