jdbc 如何打印多个查询

Question

I have a program that probes a database and prints a report of some queries. I'd like to print Department name on one line with the employee running it with all subsequent projects underneath it like so:

Administration – Jennifer S. Wallace
Computerization
Newbenefits
Headquarters – James E. Borg
Reorganization
Research – Franklin T. Wong
ProductX
ProductY
ProductZ

But the way I have it prints:

Administration Wallace S. Jennifer Computerization
Administration Wallace S. Jennifer Newbenefits
Headquarters Borg E. James Reorganization
Research Wong T. Franklin ProductX
Research Wong T. Franklin ProductY
Research Wong T. Franklin ProductZ

How Can I fix this?

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class JDBC{

   public static void main(String[] args){
      String name = "";
      String projects = "";
      
      try{
         Class.forName("com.mysql.cj.jdbc.Driver");
         Connection connection = DriverManager.getConnection("jdbc:mysql://cis-lonsmith- 
student2.ccr8ibhqw8qf.us-east-2.rds.amazonaws.com/COMPANY?useSSL=false", "user", 
"Password");
           
       Statement statement = connection.createStatement();
         ResultSet result = statement.executeQuery("SELECT Dname, Fname, Lname, Minit, 
Pname FROM DEPARTMENT, EMPLOYEE, PROJECT WHERE Mgr_ssn = Ssn AND Dnum = Dnumber GROUP BY 
Pname ORDER BY Dname;");      
      
         while(result.next()){
            
            name = result.getString("Dname") + " - " + result.getString("Lname") + " " + 
result.getString("Minit") + ". " + result.getString("Fname") + " " + 
result.getString("Pname");

            System.out.println(name);        
         }      
      }  
      catch(Exception e){
         e.printStackTrace();
      }
   }
}

Answer 1

It's difficult to guess where each column is coming from but I'll take a guess based on the wrong result you posted.

You can change the "while" section of your code to display the result as you want. It should look like:

         String title = null
         while(result.next()){
            String ltitle = 
            name = result.getString("Dname") + " - " +
              result.getString("Lname") + " " +
              result.getString("Minit") + ". " + 
              result.getString("Fname");
            String pname = result.getString("Pname");
            if (!ltitle.equals(title)) {
              System.out.println(ltitle);
              title = ltitle;
            }
            System.out.println(name);        
         }