Missing Attendance Query.

Question

HI,
I have two tables
1. attendance
2. Emp
In attendance table i have the following colums
Emp_no ,date,Present_flag
In emp table
emp_no
How to find the missing attendance......
for eg: if i pass 01-JUN-10 to 30-JUN-10 as parameter i need to get emp_no and date for which there
is no record in attendance table.
Pls help...

Answer 1

Something like this ?
SQL> ed
Wrote file afiedt.buf
  1  WITH EMPl AS (SELECT 1 empno,'A' ename FROM DUAL UNION ALL
  2               SELECT 2 empno,'B' ename FROM DUAL
  3               )
  4  ,Att AS (SELECT 1 empno,to_date('01-JUN-2010','DD-MON-YYYY') dt, 'Y' Present FROM DUAL UNION ALL
  5           SELECT 1 empno,to_date('02-JUN-2010','DD-MON-YYYY') dt, 'Y' Present FROM DUAL UNION ALL
  6           SELECT 1 empno,to_date('03-JUN-2010','DD-MON-YYYY') dt, 'Y' Present FROM DUAL UNION ALL
  7           SELECT 1 empno,to_date('05-JUN-2010','DD-MON-YYYY') dt, 'Y' Present FROM DUAL UNION ALL
  8           SELECT 1 empno,to_date('06-JUN-2010','DD-MON-YYYY') dt, 'Y' Present FROM DUAL UNION ALL
  9           SELECT 1 empno,to_date('07-JUN-2010','DD-MON-YYYY') dt, 'Y' Present FROM DUAL UNION ALL
10           SELECT 2 empno,to_date('01-JUN-2010','DD-MON-YYYY') dt, 'Y' Present FROM DUAL UNION ALL
11           SELECT 2 empno,to_date('02-JUN-2010','DD-MON-YYYY') dt, 'Y' Present FROM DUAL UNION ALL
12           SELECT 2 empno,to_date('03-JUN-2010','DD-MON-YYYY') dt, 'Y' Present FROM DUAL UNION ALL
13           SELECT 2 empno,to_date('04-JUN-2010','DD-MON-YYYY') dt, 'Y' Present FROM DUAL UNION ALL
14           SELECT 2 empno,to_date('07-JUN-2010','DD-MON-YYYY') dt, 'Y' Present FROM DUAL
15            )
16  ,date_range AS ( select to_date('01-JUN-2010','DD-MON-YYYY')-1 + level dt
17                   from dual
18                   connect by level <= (to_date('07-JUN-2010','DD-MON-YYYY') -
19                   to_date('01-JUN-2010','DD-MON-YYYY')+1 )
20                 )
21  SELECT DISTINCT b.empno,a.ename,c.dt FROM  EMPL a,Att b,date_range c
22  WHERE c.dt NOT IN (SELECT dt FROM Att inner_b where inner_b.empno=b.empno)
23  AND a.empno=b.empno
24* order by 1
SQL> /
     EMPNO E DT
         1 A 04-JUN-10
         2 B 05-JUN-10
         2 B 06-JUN-10