Print Value if No Result return by query

select coalesce(nullif(salary,-1),4) as c1 from emp;

coalesce - these function work and check data at row level.

It will ceck for each row that if column salary is null then replace value will be replcaed by 4.

Upto here it is fine for me, if any body have question in mind then they can comment on the post.

But My requirement was that if query return no result/ or zero rows then i want to print some default value.
Now as per requirement scenario has been get changed, earlier i was using coalesce function which is working at row level, now i need to control null value at dataset level

see below:
select coalesce(nullif(salary,-1),4) as c1 from emp
union
select '4'  as c1
 

BO1 Prerequisite Window Version Failed

Information: This product needs to be installed on Windows Server 2008 or a higer Windows Server Version. please verify that your version of Windows meets these requirements.

Install SAL BO 4.1 on Windows 7. Yes this is possible , u need to change one file "product.seed.xml"

• First of all extract 51046778 folder and move to below specified path 

"..\51046778\DATA_UNITS\BusinessObjectsServer_win\dunit\product.businessobjects64-4.0-core-32"

• Now open file  "product.seed.xml"
• Move to line number 1520

• Change parameter value from "server" to "Workstation"
• Save and close
• Now reinstall.

Thanks!!!!!!