Oracle/PLSQL: Avoid "data not found" error in PLSQL code

Question:  I'm a new programmer and am trying to include the following statement in my PLSQL code:

select msa_code, mda_desc, zip_code_nk
from sales.msa
where zip_code_nk = prod_rec.zip_code_nk;

When there is not a zip_code_nk in the msa table, I'm getting an oracle error saying "Data not found".

How can I code around this? It seem the processor just drops to the exception code and records the record as a failed insert.

Answer:  To prevent the PLSQL code from dropping to the exception code when a record is not found, you'll have to perform a count first to determine the number of records that will be returned.

For example:

-- Check to make sure that at least one record is returned
select count(1) into v_count
from sales.msa
where zip_code_nk = prod_rec.zip_code_nk;

if v_count > 0 then
     select msa_code, mda_desc, zip_code_nk
     from sales.msa
     where zip_code_nk = prod_rec.zip_code_nk;
end if;

If the count(1) function returns at least one record, then you can perform the "original select statement".