How to get array using Oracle sql query

Question

I want to display result set of Years between From date - To date using oracle SQL on dual table

e.g.

if i pass - From date as 1/1/1900 and To Date as 1/1/2000

then it shoold display

Only Years

1900
1901
1902
-
-

2000

Answer 1

There are two parts to this question. Generating the range of dates is quite simple: just use the trick with CONNECT BY that I demonstrated here.

edit

Generating a list of first of New Year's Days is quite simple:

SQL> select add_months(to_date('01-jan-1900'), (level-1)*12) as year
  2  from dual
  3  connect by level <= 101
  4  /

YEAR
---------
01-JAN-00
01-JAN-01
01-JAN-02
...
01-JAN-98
01-JAN-99
01-JAN-00

101 rows selected.

SQL>

You just want the years? Well either use to_char(... , 'YYYY') on that. Or cut to the chase and just generate a list of numbers from 1900 - 2000.

The trickiest part of your request is getting the number of years. It would be easier to be given a start date and an offset, rather than an end date. Anyway ...

SQL> select to_char(add_months(to_date('&&start_date'), (level-1)*12), 'YYYY') as year
  2  from dual
  3  connect by level <= ( to_number(to_char(to_date('&&end_date'), 'yyyy'))
  4                       -to_number(to_char(to_date('&&start_date'), 'yyyy')) ) + 1
  5  /
Enter value for start_date: 01-jan-1900
old   1: select add_months(to_date('&&start_date'), (level-1)*12) as year
new   1: select add_months(to_date('01-jan-1900'), (level-1)*12) as year
Enter value for end_date: 01-jan-2000
old   3: connect by level <= ( to_number(to_char(to_date('&&end_date'), 'yyyy'))
new   3: connect by level <= ( to_number(to_char(to_date('01-jan-2000'), 'yyyy'))
old   4:                      -to_number(to_char(to_date('&&start_date'), 'yyyy')) ) - 1
new   4:                      -to_number(to_char(to_date('01-jan-1900'), 'yyyy')) ) - 1


YEAR
----
1900
1901
1902
...
1998
1999
2000

101 rows selected.

SQL>