Check a record IS NOT NULL in plsql
I have a function which would return a record with type my_table%ROWTYPE
, and in t开发者_运维知识库he caller, I could check if the returned record is null, but PL/SQL complains the if-statement that
PLS-00306: wrong number or types of arguments in call to 'IS NOT NULL'
Here is my code:
v_record my_table%ROWTYPE;
v_row_id my_table.row_id%TYPE := 123456;
begin
v_record := myfunction(v_row_id)
if (v_record is not null) then
-- do something
end if;
end;
function myfunction(p_row_id in my_table.row_id%TYPE) return my_table%ROWTYPE is
v_record_out my_table%ROWTYPE := null;
begin
select * into v_record_out from my_table
where row_id = p_row_id;
return v_record_out;
end myfunction;
Thanks.
As far as I know, it's not possible. Checking the PRIMARY KEY
or a NOT NULL
column should be sufficient though.
You can check for v_record.row_id IS NULL
.
Your function would throw a NO_DATA_FOUND
exception though, when no record is found.
You can't test for the non-existence of this variable so there are two ways to go about it. Check for the existence of a single element. I don't like this as it means if anything changes your code no longer works. Instead why not just raise an exception when there's no data there:
I realise that the others
in the exception is highly naughty but it'll only really catch my table disappearing when it shouldn't and nothing else.
v_record my_table%ROWTYPE;
v_row_id my_table.row_id%TYPE := 123456;
begin
v_record := myfunction(v_row_id)
exception when others then
-- do something
end;
function myfunction(p_row_id in my_table.row_id%TYPE) return my_table%ROWTYPE is
v_record_out my_table%ROWTYPE := null;
cursor c_record_out(c_row_id char) is
select *
from my_table
where row_id = p_row_id;
begin
open c_record_out(p_row_id);
fetch c_record_out into v_record_out;
if c_record_out%NOTFOUND then
raise_application_error(-20001,'no data);
end if;
close c_record_out;
return v_record_out;
end myfunction;
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