Question

Dear Programmers,
I need to compare one column value to another column in single select query.

As my query goes like this:

    SELECT ATTNLOG.emp_id,
           ATTNLOG.tdate,
           ATTNLOG.tdate_out,
          (CASE WHEN EXISTS (SELECT * 
                               FROM tbl_emp_overtime 
                              WHERE emp_id=ATTNLOG.emp_id 
                                AND ot_indate=ATTNLOG.tdate)
               THEN 0 
               ELSE 1 
          END) as 'STATUS'
    FROM tbl_emp_attn_log ATTNLOG 
   WHERE ATTNLOG.emp_id=201

In my case condition i need to compare the every row of ATTNLOG and gives STATUS respectively.

Actually the result returns row values like

EMP_ID  TDATE     TDATE_OUT  STATUS
201    2012-2-26  2012-2-26   0
201    2012-2-27  2012-2-27   1

and the table tbl_emp_overtime has value like

emp_ID  ot_indate
201    2012-2-27

But my code gives like

EMP_ID  TDATE     TDATE_OUT  STATUS
201    2012-2-26  2012-2-26   1
201    2012-2-27  2012-2-27   1

But it don’t give the result like that. Please help me out.

Answer 1

If you use sql 2008 cast the dates to date data type, if the original data type is datetime it should help:

SELECT * 
FROM tbl_emp_overtime 
WHERE emp_id=ATTNLOG.emp_id 
AND CAST(ot_indate as DATE)=CAST(ATTNLOG.tdate AS DATE)