接分：jdbc连接oracle数据库，可以进行查询操作，但是不能进行插入操作。为什么？

import lotus.domino.*;
import java.sql.*;
public class JavaAgent extends AgentBase {
Document doc;
Database db;

public void NotesMain() {

try{
Session session = getSession();
AgentContext agentContext = session.getAgentContext();

db=agentContext.getCurrentDatabase();
doc=agentContext.getDocumentContext();

//Class.forName( "oracle.jdbc.driver.OracleDriver" );
//JDBC-ODBC桥驱动程序
//String driverName="sun.jdbc.odbc.JdbcOdbcDriver";
Driver c = new sun.jdbc.odbc.JdbcOdbcDriver();
DriverManager.registerDriver(c);
//Oracle Jdbc驱动
//String driverName="sun.jdbc.odbc.JdbcOdbcDriver";

String connectionURL="jdbc:odbc:jzunicom";

String strUserName="UNICOM";
String strPassword="UNICOM";
Connection con=null;
Statement stmt=null;
ResultSet rs = null;

String str1,str2,str3,str4,test;
str1 = "insert into unicom.user_info(name,job,depart,CellPhoneNumber,LoginName,Password) values('";
str2 = doc.getItemValueString("LastName")+"','"+doc.getItemValueString("job")+"','";
str3 = doc.getItemValueString("depart")+"','"+doc.getItemValueString("CellPhoneNumber")+"','";
str4 = doc.getItemValueString("FullName")+"','"+doc.getItemValueString("Password")+"')";
String sqlStatement=str1+str2+str3+str4;
System.out.println(sqlStatement);
try
{
//Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
if (con==null){
con = DriverManager.getConnection(connectionURL,strUserName,strPassword);
stmt = con.createStatement();
stmt.execute(sqlStatement);
}

}
catch(Exception ex)
{
ex.printStackTrace();
}
stmt.close();
con.close();
con=null;
}
catch(Exception ex)
{
ex.printStackTrace();
}
}
}