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import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class Update {
public static void main(String[] args) throws SQLException {
// TODO Auto-generated method stub
query("iuoi");//空指针异常
}
public static void delete() throws SQLException
{
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Connection conn = null;
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/jdbc1","root","");
ResultSet rs=null;
String query = "select * from exam_student";
String delete ="delete from exam_student where height=165";
PreparedStatement pr = conn.prepareStatement(delete);
int i = pr.executeUpdate();
rs=pr.executeQuery(query);
while(rs.next())
{
//System.out.println(pr.executeUpdate());
System.out.println(rs.getObject(1)+" "+i);
}
}
public static void query(String name) throws SQLException
{
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Connection conn = null;
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/jdbc1","root","");
Statement st = null;
ResultSet rs=null;
String query = "select name,str_no,height from exam_student where name='"+name+"'";
//String delete ="delete from exam_student where height=165";
//PreparedStatement pr = conn.prepareStatement(delete);
//int i = pr.executeUpdate();
rs=st.executeQuery(query);//此处抱空指针异常
while(rs.next())
{
//System.out.println(pr.executeUpdate());
System.out.println(rs.getObject(1)+" "+rs.getObject(2)+" "+rs.getObject(3));
}
}
}