ТЕМА:

declare
n number := 0;
begin
select 1
into n from table1 where pid=111 ;
return(n);
exception
when no_data_found then
n := 0;
return(n);
when Others Then
n := -1 * sqlcode;
return(n);
end;

select 1 from dual

where exists ( select null from payment_table p

               where p.pid = 111);

select 1 from dual

where exists ( select null from payment_table p

               where p.pid = 111)

union all

select 0 from dual

where not exists ( select null from payment_table p

                   where p.pid = 111);

select count(pid) into c1 from table1 where (pid=111);

c1=0 - нет записей,
с1>0 - есть записи.

select decode(count(pid),0,0,1) into c1 from table1 where (pid=111);

c1=0 - нет записей,
с1=1 - есть записи.