PL/SQL check if query returns empty

Question

I\'m writing a procedure, and i need to check whether my select query returned an empty record or not. (In this example whether there is no x,y shelf)

How can i do t

Answer 1

catch first not wanted condition and use count(1) because count(*) actually trying to count something and add rownum=1, you need only one first not matching condition. i use this statement.

       declare
      v_check number;
    begin
      select count(1) into v_check 
from table
 where condition(something not wanted) AND rownum=1;

      if v_check = 0 then 
           --do something else
      elsif v_check = 1 --dont want theat
         rise some error or more..
      end if;
    end;

For you just

select count(1) into v_check from dual where exists (select count(1) 
    from table
     where condition AND rownum=1);

if v_check = 0 then --nothing found
                 something...
          elsif v_check = 1 --found something
            something...
          end if;
        end;