Problems with report using isql*plus

Question

Hi there,
As the title of this topic illustrates, i'm having trouble dumping relevant data from columns of different tables. Using isql*plus, I have three tables appropriatly related. A 'course' table, 'student' and 'next_of_kin' tables. I have many students enrolled on various courses but only a hanfull of courses offer the module option 'Database Systems'. I have no 'module' table but i know the three course names which provide the module option. I intend on producing a report hich lists all students enrolled on the courses which provid the module option 'Database Systems'. I have attempted the report but i keep getting a 'cartesian product' displaying all next_of_kin names instead of the appropriate. Also i am struggling to come up with the right WHERE statement to depict only the three courses which provide the module option 'Database Systems' as defined by 'courseNo' in both 'course' and 'student' tables.
Here is the most recent attempt:
--set echo off*
--set pagesize 24*
--set feedback off*
--set linesize 78*
col A format 99999999 heading 'Student No'
col B format A15 heading 'Student Name'
col C format A15 heading 'Course Name'
col D format 99999999 'Course No'
col E format A10 heading 'Next-of-Kin'
break on A skip 1 on B
TTitle 'Business Studies 1 Option BT300'
BTitle 'Prepared By : Richard Stroud / 20527796'
Select student.StudentNo "Student No",
student.fName || ' ' || student.lName "Student Name",
course.title "Course Name",
course.courseNo "Course No",
next_of_kin.fName || ' ' || next_of_kin.lName "Next-of-Kin"
From student, course, next_of_kin
where course.courseNo = '12885545'
order by studentNo
--clear columns*
--TTitle off*
--BTitle off*
--set feedback on*
--set pagesize 24*
--clear breaks*
Any help towards this toipic will be GREATLY appreciated

Answer 1

According to my little knowledge - i don't think Oracle is an AIDB. It is only RDBMS or rather you can call it Advanced RDBMS.
Now, you are thinking that since you have provided the relavant table here - so Oracle should automatically pic the single records. Since you have define every logic including the concept of primary key, foreign key in your table.
But, question is - did you apply the relationship in your join between the tables.
What does a primary key, foreign key do inside a table? Is it automatically select the unique rows from the join tables - when you didn't mention the join criterion.
If you think that - then you are wrong. My advice is - kindly go through the JOIN Concept.
Then start your coding. This is very dangerous way to start. Learn the basics at least.
So, what Senti suggested has a very much valid point.
Regards.
Satyaki De.