hello every 1
can any one tell me ?

the most likekly cause for slow execution of the statement.

here are the table and qeury

Table one
module(module_id int, department char(15));

Table two
student(student_id int, name char(15), gender char(5));

Table three
Create table module_student(module_id int, student_id int, date_attended char(5));

Statment

Select distinc s.student_id
From module m, module_student ms, student s
Where m.module_id=m.ms.module_id
And s.gender=’M’
And m.department = ‘Computer science’;

many thanx
akshay

If you have a large number of records in the tables, and the tables don't have any indexes, your query will run slow. Also I noticed that 'Computer science' is 16 characters long, and your quering a 15 character field.

Hope this helps.