If condition in PL/SQL script with cursor and loop - oracle

Question

I would like to ask for some help or advice in this particular case.
I have table called "Teams". The table contains 3 columns - Issue, Responsible_team and More_Info (all varchar2).
I have a PL/SQL script with cursor and loop for selecting as many teams as issue description you type (some random word you think it might help you find the responsible team). This part works great for me.
But I do not know how to compile the IF condition in there. If no team is found according to typed word description, I would like to get some basic output dbms_output.put_line('Responsible team is not found').
There are 2 ways how I wrote the script. Classic loop and while loop.
I would be happy for any advice.
1.script
set verify off
DECLARE
v_issue teams.issue%type; --variable for issue column from teams table
v_respteam teams.responsible_team%type; --variable for responsible_team column from teams table
v_info teams.more_info%type; --variable for more_info column from teams table
--cursor declaration
CURSOR c_respteam
RETURN teams%ROWTYPE
IS
SELECT issue, responsible_team, more_info
FROM teams
WHERE lower(issue) like '%&Describe_Issue%';
BEGIN
OPEN c_respteam;
LOOP
FETCH c_respteam into v_issue, v_respteam, v_info;
EXIT when c_respteam%NOTFOUND;
dbms_output.put_line('Responsible team is '|| v_respteam || ' --> ' || v_info);
END LOOP;
CLOSE c_respteam;
end;
/
2.script
-- cursor with while loop
set verify off
DECLARE
v_issue teams.issue%type; --variable for issue column from teams table
v_respteam teams.responsible_team%type; --variable for responsible_team column from teams table
v_info teams.more_info%type; --variable for more_info column from teams table
CURSOR c_respteam
RETURN teams%ROWTYPE IS
SELECT issue, responsible_team, more_info
FROM teams
WHERE lower(issue) like '%&Describe_Issue%';
BEGIN
OPEN c_respteam;
FETCH c_respteam INTO v_issue, v_respteam, v_info;
WHILE c_respteam%FOUND
LOOP
dbms_output.put_line('Responsible team is '|| v_respteam || ' --> ' || v_info);
FETCH c_respteam INTO v_issue, v_respteam, v_info;
END LOOP;
CLOSE c_respteam;
END;
/

Answer 1

You could rewrite to:
declare
l_found boolean :=false;
cursor c_respteam is
select issue
,responsible_team
,more_info
from teams
where lower(issue) like '%&Describe_Issue%';
begin
for r in c_respteam
loop
l_found := true;
dbms_output.put_line('Responsible team is ' || r.responsible_team || ' --> ' || r.more_info);
end loop;
if not l_found
then
dbms_output.put_line('No records found');
end if;
end;
/

Answer 2

You need to have a counter variable [ETA: ooh, I like Rene's boolean variable idea instead; either way, you need an extra variable!] to work out if any rows were returned or not. I'm not sure why you're using an explicit cursor fetch, rather than using the cursor-for-loop? Cursor-for-loops are not only easier to write, read and maintain, but Oracle have put some behind-the-scenes optimisation in, to aid performance.
Of course, depending on what you're actually doing with the data returned by your cursor (dbms_output.put_line being something that you should never have in your production code), it's debatable that you would need to loop through a cursor at all.
Anyway, with that said, here's an example demonstrating how I would handle your requirement to check for no rows returned by the cursor:
declare
cursor cur (p_val varchar2)
is
select dummy
from dual
where dummy like '%'||p_val||'%';
v_counter integer := 0;
begin
for rec in cur('Y')
loop
dbms_output.put_line('value of dummy = '||rec.dummy);
v_counter := v_counter + 1;
end loop;
if v_counter = 0 then
dbms_output.put_line('no rows returned');
end if;
end;
/
no rows returned
declare
cursor cur (p_val varchar2)
is
select dummy
from dual
where dummy like '%'||p_val||'%';
v_counter integer := 0;
begin
for rec in cur('X')
loop
dbms_output.put_line('value of dummy = '||rec.dummy);
v_counter := v_counter + 1;
end loop;
if v_counter = 0 then
dbms_output.put_line('no rows returned');
end if;
end;
/
value of dummy = X
To expand on what I said in my comment below, it sounds like you just need a single sql statement, rather than using PL/SQL and relying on dbms_output.
Eg., say you have the following statement:
select lvl
from (select 'X'||level lvl from dual connect by level <= 10)
where lvl like '%&val%';
with &val blank, you get:
LVL
-----------------------------------------
X1
X2
X3
X4
X5
X6
X7
X8
X9
X10
With &val = 2 you get:
LVL
-----------------------------------------
X2
With &val = 100 you get:
no rows selected.