Question

my query is something like this

Select date_value from Tab1;

The output looks like this (date_value is a Varchar2 column)

 2008-2009
 2009-2010
 2007-2009

I am trying to some formatting on the column date_value,so that the output looks like this

 2008-09
 2009-10
 2007-09

Is there a way to do this as part of the above query using some Split/Join inbuilt oracle functions. I was exploring about Instr and Substr, but i am not sure how to do this jsut in that query.

Answer 1

If you’re doing this on a 10g database you can use Regular Expressions.

SQL> select dcol
  2         , regexp_replace(dcol
  3                          , '([[:digit:]]+)\-([[:digit:]]{2})([[:digit:]]{2})'
  4                          , '\1-\3') as regexp_replace
  5  from t79
  6  /

DCOL                           REGEXP_REPLACE
------------------------------ ------------------------------
2008-2009                      2008-09
2009-2010                      2009-10
2007-2009                      2007-09

SQL>

Of course, the usual caveat about regex applies here, although it does have one distinct advantage: Y10K compliance 🙂

SQL> select dcol
  2         , regexp_replace(dcol
  3                          , '([[:digit:]]+)\-([[:digit:]]+)([[:digit:]]{2})'
  4                          , '\1-\3') as regexp_replace
  5  from t79
  6  /

DCOL                           REGEXP_REPLACE
------------------------------ ------------------------------
2008-2009                      2008-09
2009-2010                      2009-10
2007-2009                      2007-09
10199-10200                    10199-00
887-888                        887-88

SQL>