>empl_no WEF Salary >0001 01/01/1998 2000 >0001 01/01/1999 2500 >0001 01/01/2000 3000 >0001 01/02/2001 3200 >>How can I construct a SQL to generate follwing cursor
>empl_no WEF New Salary Old Salary
>0001 01/01/1998 2000 NULL
>0001 01/01/1999 2500 2000
>0001 01/01/2000 3000 2500
>0001 01/01/2001 3200 3000
>
>Would appreciate all help. ThanksSELECT a.empl_no,a.wef,a.salary AS new_salary,b.salary AS old_salary FROM salary a; LEFT JOIN salary b ON a.empl_no = b.empl_no AND a.wef > b.wef; GROUP BY a.empl_no,a.wef