if my query returns empty i want to display input as output

Try this: (not tested)

IF NOT EXISTS (select ci_id from category where parent_id =236282
UNION
select ci_id from category where parent_id in(select category_id from
category where parent_id=236282)
)
BEGIN 
  SELECT 236282
END
ELSE 
BEGIN
(select ci_id from category where parent_id =236282
UNION
select ci_id from category where parent_id in(select category_id from
category where parent_id=236282)
)
END

Select allOpen in new window

Try

select isnull(ltrim(ci_id),'236282') from
(select ci_id from category where parent_id =236282
UNION
select ci_id from category where parent_id in(select category_id from
category where parent_id=236282)) a

Select allOpen in new window

hi HuaMinChen,

the above query is not working

I got the solution for this query.

SELECT      * FROM      category WHERE      parent_id = 236282       OR parent_id IN (                   SELECT      category_id                   FROM      category                   WHERE       parent_id = 236282             );

which lists all children and grandchildren of the given id (same as the query you posted originally)

not sure about this : "i want to display 236282 as the output if my query returns empty" or what you actually wanted in the first place

good for you if you got it working

ps : you can accept your own answer if you don't want to spend your points

Hi skullnobrains,

i am getting the expected result from the second query as u posted

THANKS

Thanks,but it is  too late
Please look into my new question posted recently.
https://www.experts-exchange.com/questions/28729520/how-do-i-modify-this-mysql-query.html
https://www.experts-exchange.com/questions/28732500/how-to-get-the-count-query-from-the-below-query.html