Select Query to achieve specified output (Script given)

Question

Hello all,
SOURCE DATA
Given below is the data present in the table:
EMP_ID YEAR SAL
10 1997 1400.00
10 2001 1500.00
10 2003 1600.00
10 2004 1700.00
10 2006 1800.00
20 2003 2500.00
20 2005 2800.00
20 2006 3000.00
REQUIREMENT
Write a select query to return rows with consecutive years,
if in case the year is not present for a particular employee
then that year must be populated with the previous years's data of the same employee
example - For the employee 10, for the years 1998, 1999, 2000 are populated
with the data of 1997
Pls let me know if you need any information from my end.
Thank you.
EMP_ID YEAR SAL
10 1997 1400.00
10 1998 1400.00
10 1999 1400.00
10 2000 1400.00
10 2001 1500.00
10 2002 1500.00
10 2003 1600.00
10 2004 1700.00
10 2005 1700.00
10 2006 1800.00
20 2003 2500.00
20 2004 2500.00
20 2005 2800.00
20 2006 3000.00
SCRIPT:
CREATE TABLE temp (
emp_id NUMBER(4),
year NUMBER(4),
sal NUMBER(10,2),
CONSTRAINT pk_temp PRIMARY KEY (emp_id, year)
INSERT INTO temp (emp_id, year, sal) VALUES (10, 1997, 1400);
INSERT INTO temp (emp_id, year, sal) VALUES (10, 2001, 1500);
INSERT INTO temp (emp_id, year, sal) VALUES (10, 2003, 1600);
INSERT INTO temp (emp_id, year, sal) VALUES (10, 2004, 1700);
INSERT INTO temp (emp_id, year, sal) VALUES (10, 2006, 1800);
INSERT INTO temp (emp_id, year, sal) VALUES (20, 2003, 2500);
INSERT INTO temp (emp_id, year, sal) VALUES (20, 2005, 2800);
INSERT INTO temp (emp_id, year, sal) VALUES (20, 2006, 3000);
COMMIT;
Thanks and Regards,
Muthu
Message was edited by:
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Answer 1

Hi,
What about this :
  1  select emp.emp_id, emp.year,
  2         case when temp.sal is null then (select max(sal) keep (dense_rank last order by year)
  3                                          from   temp
  4                                          where  emp.emp_id=temp.emp_id
  5                                          and    emp.year>temp.year
  6                                          and    temp.sal is not null)
  7     else temp.sal end sal
  8  from
  9  (select emp_year.emp_id, y.year
10   from (select emp_id,
11                min(year) min_year,
12                max(year) max_year
13         from temp group by emp_id) emp_year,
14   (select min_year+rownum-1 year
15    from (select min(year) min_year, max(year) max_year from temp)
16    connect by level <=max_year-min_year+1) y
17   where y.year>=emp_year.min_year
18   and   y.year<=emp_year.max_year) emp,
19  temp
20  where emp.emp_id=temp.emp_id(+)
21  and   emp.year=temp.year(+)
22* order by 1,2
SQL> /
    EMP_ID       YEAR        SAL
        10       1997       1400
        10       1998       1400
        10       1999       1400
        10       2000       1400
        10       2001       1500
        10       2002       1500
        10       2003       1600
        10       2004       1700
        10       2005       1700
        10       2006       1800
        20       2003       2500
        20       2004       2500
        20       2005       2800
        20       2006       3000
14 rows selected.
SQL> select * from temp order by 1,2;
    EMP_ID       YEAR        SAL
        10       1997       1400
        10       2001       1500
        10       2003       1600
        10       2004       1700
        10       2006       1800
        20       2003       2500
        20       2005       2800
        20       2006       3000
8 rows selected.Nicolas.