Order by clause...

Question

Hi everyone,
How can i achieve this with order by clause
If i have the following data in my table. I need one record (which has the data 'Last record')
to be the last record for my select statement, and order the other records according to "no"
whatever data i have i need to arrange that record last
select * from
select 'A' order_by_test,5 no  from dual
union all
select 'B' order_by_test,1 no from dual
union all
select 'C' order_by_test,8 no from dual
union all
select 'Last record' order_by_test,3 no from dual
union all
select 'Z' order_by_test,7 no from dual
union all
select null order_by_test,null no from dual
union all
select '  ' order_by_test,null no from dual
output:
=======
order_by_test     no
    B             1         -->other records ,order by no nulls last
    A             5
    Z             7
    C             8
   null           null
  '  '            null
  Last record     3      ----> everytime this should be the last record of my select statement,I am sorry if it is a dumb question to ask.
Thanks in advance

Answer 1

Hi,
Use CASE (or equivalents) to map your values into sortable values.
ORDER BY  CASE
                 WHEN  order_by_test = 'Last record'
           THEN  2
           ELSE  1
             END
,       noIf the sort order depends on two different columns, it's often best to have two different expressions in the ORDER BY clause.
SET     NULL     [NULL]
select * from
select 'A' order_by_test,5 no  from dual
union all
select 'B' order_by_test,1 no from dual
union all
select 'C' order_by_test,8 no from dual
union all
select 'Last record' order_by_test,3 no from dual
union all
select 'Z' order_by_test,7 no from dual
union all
select null order_by_test,null no from dual
union all
select '  ' order_by_test,null no from dual
ORDER BY  CASE
                 WHEN  order_by_test = 'Last record'
           THEN  2
           ELSE  1
             END
,       no
ORDER_BY_TE         NO
B                    1
A                    5
Z                    7
C                    8
            [NULL]
[NULL]      [NULL]
Last record          3Edited by: Frank Kulash on Mar 31, 2010 1:20 PM
Added full query and output