Using function on decode or case in query

Question

Hi experts
I am using oracle 11G database,I have to check length of name column value from employee table and if length(name) > 39 then value should be substr(name,0,39)
else value should be name only.
i tried below code
select CASE when length(name) > 39,substr(name,0,39)
            else name
       END
  from employee but its not working ..can I do this using decode too ? ,,which one would be better or this is not a right way ?
Thanks

Answer 1

Hi,
siebelD wrote:
Hi experts
I am using oracle 11G database,I have to check length of name column value from employee table and if length(name) > 39 then value should be substr(name,0,39)
else value should be name only.
i tried below code
select CASE when length(name) > 39,substr(name,0,39)
else name
END
from employee but its not working ..Review the syntax of the CASE expression in the SQL Language manual. A CASE expression always has at least one THEN clause. Commas are not part of the CASE expression syntax.
can I do this using decode too ? Sure, anything you can do with CASE you can also do with DECODE.
,,which one would be betterThis is one of the many situations where CASE is much shorter, clearer and more efficient than DECODE.
or this is not a right way ?How about
SELECT  SUBSTR (name, 1, 39)  AS employee_name
FROM    employee;?
If name is 39 characters (or less), then <tt> SUBSTR (name, 1, 39) </tt> will return it, unchanged.
Edited by: Frank Kulash on Mar 3, 2013 2:07 PM