OBJECT

If database table created with column type as objects, it can hold more than one value of different types. Syntax - 

create type <typename> as object (<columnname> <type>, <columnname> <type>......);

SQL> create type add_type as object(street varchar2(20), city varchar2(20));

SQL> create table person(name varchar2(20), address add_type);

SQLData

It is an interface. The interface used for custom mapping of an SQL user-defined type (UDT) to a class in the java programming language. The class object for a class implementing the SQLData interface will be entered in the appropriate connection objects type map along with the SQL name of the UDT for which it is a custom mapping.

Methods

1. String getSQLTypeName() - Returns fully qualified name of the SQL user-defined type that this object represents.
2. void readSQL(SQLInput stream, String typename) - Populates this object with data read from the database.
3. void writeSQL(SQLOutput stream) - Writes this object to the given SQL data stream, converting it back to its SQL value in the data source.

PROGRAM TO INSERT RECORD USING OBJECT IN DATABASE

package Package1;

import java.sql.*;

public class Address implements SQLData{

private String street;

private String city;

private String sqltype;

public Address(String street, String city, String sqltype) {

super();

this.street = street;

this.city = city;

this.sqltype = sqltype;

}

@Override

public String getSQLTypeName() throws SQLException {

return sqltype;

}

@Override

public void readSQL(SQLInput stream, String typeName) throws SQLException {

street=stream.readString();

city=stream.readString();

this.sqltype=sqltype;

}

@Override

public void writeSQL(SQLOutput stream) throws SQLException {

stream.writeString(street);

stream.writeString(city);

}

}

-------------------------------------------------------

package Package1;

import Package1.Address;

import java.sql.*;

public class WriteObjectTest {

public static void main(String[] args) throws ClassNotFoundException, SQLException {

Class.forName("oracle.jdbc.driver.OracleDriver");

Connection con = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl", "scott", "rakesh");

PreparedStatement ps = con.prepareStatement("insert into person values(?,?)");

ps.setString(1,"rakesh");

Address a = new Address("Bamunimaidam", "Guwahati", "ADD_TYPE");

ps.setObject(2, a);

int count=ps.executeUpdate();

System.out.println(count);

}

}

Output -

NAME

--------------------

ADDRESS(STREET, CITY)

rakesh

ADD_TYPE('Bamunimaidam', 'Guwahati')