Class.forName("com.mysql.jdbc.Driver");
String url = "jdbc:mysql://localhost:3306/mysql";
String user = "root";
String userpassword="123456";
Connection connection = DriverManager.getConnection(url, user, userpassword);
String sql="select teacher_id from t_teacher where teacher_name = zhangsan";
Statement state = connection.createStatement();
ResultSet rs= state.executeQuery(sql);
while(rs.next()) {
id= rs.getString("teacher_id");
}
String sql="select * from t_teacher where teacher_name = ? and password = ? ";
Connection connection = DriverManager.getConnection(url, username,userpassword);
PreparedStatement prepareState = connection.prepareStatement(sql);
prepareState.setString(1,name);
prepareState.setString(2,password);
ResultSet rs=prepareState.executeQuery();
int rs = prepareState.executeUpdate();
boolean rs = preapareState.execute();