(Merge) Compress multile rows into one

Question

Hello,
I have a little problem with an sql statement.
First I have a table storing Projects. Second I have a table storing emplyees. Multiple emps can work on one project. For this i have one row with a reference to the emp in each project. If there is an existing row in the project table i know, that this emp works for this project.
Now I want to create a query which returns me one row per project with a X in the columns of the emp.
Like the following (this should be the result):
Projectname     Emp A    Emp B    Emp C
=======================================
Project A       X        X
Project B       X        X        X
Project C                X        XAs there are multiple rows in each project which are not equal, i could not use DISTINCT or GROUP BY?!
But how can I solve this? The problem is that I have to query this in one SQL query and I could not use PL/SQL or a custom function.
Thanks,
Thomas
Message was edited by:
thomasw

Answer 1

OK, I try:
Project table:
Column Name:      Data Type:
pro_id                   NUMBER (10,0)
name                    VARCHAR2(2000)
description            VARCHAR2(2000)
Content:
pro_id     name      description
================================
1            Test        ...
2            Foo         ...
3            Bar         ...
4            Further    ...Employee table:
Column Name:      Data Type:
emp_name_id       NUMBER (10,0)
emp_pro_id          NUMBER(10,0)
Content:
emp_name_id       em_pro_id
==========================
1                         1
2                         1
4                         2
1                         3
2                         4
3                         3
1                         4
4                         4Result:
pro_id     emp1   emp2   emp3   emp4
===========================
1            X                X       X
2            X                          X
3                             X
4                     X               XI hope this will help!
Thanks,
Thomas