single-row sub query return more than one row in procedure - oracle10g

Question

procedure below throws exception
single-row sub query return more than one row
while executing query on sql> query execute fine and shows result
as expected
create or replace procedure discount_purchase(cust_name customer1.cust_name%type)
as
amt int;
discount int;
begin
select sum(purch_amt) into amt
from orders
where customer_id=(select customer_id from customer1 where cust_name=cust_name);
dbms_output.put_line('Total amount is='||amt);
if(amt>=500) then
discount:=amt-(0.25*amt);
dbms_output.put_line('Discount amount is='||discount);
else
dbms_output.put_line('NO Discount on='||amt||'Discount only above 500');
end if;
end;
/
­
SQL> exec discount_purchase('Nick Rimando');
BEGIN discount_purchase('Nick Rimando'); END;
*
ERROR at line 1:
ORA-01427: single-row subquery returns more than one row
ORA-06512: at "ARPAN.DISCOUNT_PURCHASE", line 6
ORA-06512: at line 1

Answer 1

The problem is that you have multiple customers in the customer1 table with the cust_name of 'Nick Rimando'. Have a look at
select count(1)
from customer1
where cust_name = 'Nick Rimando';
I bet it will result in a number higher than 1.
The fix(es)
The fix depends on what you actually need. And you actually did not write what you need. So, a few cases come to my mind...
Case 1 - Sum of purchases of all customers with that name
create or replace procedure discount_purchase(cust_name customer1.cust_name%type)
as
amt int;
discount int;
begin
select sum(purch_amt) into amt
from orders
where customer_id in (select customer_id from customer1 where cust_name=cust_name);
dbms_output.put_line('Total amount is='||amt);
if(amt>=500) then
discount:=amt-(0.25*amt);
dbms_output.put_line('Discount amount is='||discount);
else
dbms_output.put_line('NO Discount on='||amt||'Discount only above 500');
end if;
end;
/
Case 2 - Sum of purchases of arbitrary single customer with that name
create or replace procedure discount_purchase(cust_name customer1.cust_name%type)
as
amt int;
discount int;
begin
select sum(purch_amt) into amt
from orders
where customer_id = (select customer_id from customer1 where cust_name=cust_name and rownum <= 1);
dbms_output.put_line('Total amount is='||amt);
if(amt>=500) then
discount:=amt-(0.25*amt);
dbms_output.put_line('Discount amount is='||discount);
else
dbms_output.put_line('NO Discount on='||amt||'Discount only above 500');
end if;
end;
/
Case 3 - Sum of purchases of "the first" customer with that name
create or replace procedure discount_purchase(cust_name customer1.cust_name%type)
as
amt int;
discount int;
begin
select sum(purch_amt) into amt
from orders
where customer_id = (select min(customer_id) from customer1 where cust_name=cust_name);
dbms_output.put_line('Total amount is='||amt);
if(amt>=500) then
discount:=amt-(0.25*amt);
dbms_output.put_line('Discount amount is='||discount);
else
dbms_output.put_line('NO Discount on='||amt||'Discount only above 500');
end if;
end;
/
Case 4 - you choose, you implement
I can't tell you how, that is solely up to you and your design considerations.
Case 5 - Fix your data model
Again, I can't tell you how, that is solely up to you and your design considerations.