Comments on: SQL – RANK, MAX Analytical Functions, DECODE, SIGN

By: http://etllabs.com/

http://etllabs.com/ — Sun, 05 Feb 2012 15:40:05 +0000

It’s very clean explanation with progressive teaching approach, nce explanation on Oracle Decode

By: Charles Hooper

Charles Hooper — Sun, 27 Dec 2009 12:52:08 +0000

Great idea, thanks for the suggestion. I agree that the CASE structure is easier to understand (and maintain) than the equivalent DECODE structure in a SQL statement like the one used in this blog post.

By: jametong

jametong — Sun, 27 Dec 2009 06:32:37 +0000

for this type of question, I will prefer to user case instead of decode and sign..

SQL> SELECT
  2    SYMBOL,
  3    MAX(ORDERS) OVER (PARTITION BY SYMBOL) ORDERS,
  4    TTIME TTIME,
  5    case
  6      when TTIME >= 9450 and ttime <= 15300 then 10
  7      else 1
  8    end extra_sort
  9  FROM
 10    T1;

S     ORDERS      TTIME EXTRA_SORT
- ---------- ---------- ----------
A          2       9300          1
A          2       9450         10
A          2      10300         10
A          2       9451         10
A          2      15300         10
A          2      17000          1
A          2      16000          1
B          4      16000          1
B          4       9300          1
C          3      16000          1

10 rows selected.