74 Advanced Java Tutorial |JDBC | ParameterMetadata | Java Database Connectivity | adv java

Advanced Java JDBC Tutorial : adv java : ParameterMetaData:
Java Database Connectivity
Gives information/details about the parameters (?) placed in the sql query of JDBC PreparedStatement object.

- ParameterMetaData object means it is the object of a jdbc driver supplied java class that implements java.sql.ParameterMetaData interface.

-to create the object:
PreparedStatement ps =con.prepareStatement("insert into student values( ?,?,?)");
ParameterMetaData pmd=ps.getParameterMetaData();

using 'pmd' we can gather info about parameters (?).

Very few JDBC drivers are giving support for ParameterMetaData, like Oracle thin, oci, Connecctor J drivers are giving any kind of support for ParameterMetaData.

Java JDBC example application on ParameterMetaData :
-----------------------------------------------------
(recommended to work with type 1 Driver)
import java.sql.*;
public class ParameterMetaDataTest
{
public static void main(String[] args) throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
//sun.jdbc.odbc.JdbcOdbcDriver
Connection con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl", "scott", "boss");

//jdbc:odbc:oradsn /mssqldsn

PreparedStatement ps=con.prepareStatement("insert into student values(?,?,?)");
ParameterMetaData pmd=ps.getParameterMetaData();

System.out.println("implemented subclass name of java.sql.ParemeterMetaData interface is :"+pmd.getClass().getName());

int cnt=pmd.getParameterCount();
for (int i=1;i less than=cnt ;i++ )
{
System.out.println("Paremeter number is :"+i);
System.out.println("Mode is :"+pmd.getParameterMode(i));
System.out.println("Type :"+pmd.getParameterType(i));
System.out.println("Type Name :"+pmd.getParameterTypeName(i));
System.out.println("Precision is :"+pmd.getPrecision(i));
System.out.println("Scale is :"+pmd.getScale(i));
System.out.println("Nullable ? is :"+pmd.isNullable(i));
System.out.println("Signnd :"+pmd.isSigned(i));
}
}
}