Select into variables from cte using if oracle - oracle

Question

I need to save values from cte into variables in the procedure.
My example:
WITH test_cte AS (
SELECT *
from(
SELECT date_a,lastName,firstName,birthDate, rank() over(ORDER BY date_a desc) rnk
FROM test_table a
join test_table b ON b.id = a.bid
)a1
WHERE rnk =1)
SELECT count(*) into count_a
FROM test_table a
join test_table b ON b.id = a.bid
WHERE a.code = code_name;
IF count_a > 0 THEN
SELECT date_a,lastName,firstName,birthDate
into date_a_var,lastName_var,firstName_var,birthDate_var
FROM test_cte;
ELSE
date_a_var := NULL;
lastName_var := NULL;
firstName_var := NULL;
birthDate_var := NULL;
END IF;
but when I try to compile it I'm getting next error:
PL / SQL: ORA-00942: table or view does not exist
on FROM test_cte;
What can I do to solve this problem?

Answer 1

In your code:
-- Start of first SELECT statement.
WITH test_cte AS (
SELECT *
from(
SELECT date_a,lastName,firstName,birthDate, rank() over(ORDER BY date_a desc) rnk
FROM test_table a
join test_table b ON b.id = a.bid
)a1
WHERE rnk =1
)
SELECT count(*) into count_a
FROM test_table a
join test_table b ON b.id = a.bid
WHERE a.code = code_name;
-- End of first SELECT statement.
IF count_a > 0 THEN
-- Start of second SELECT statement.
SELECT date_a,lastName,firstName,birthDate
into date_a_var,lastName_var,firstName_var,birthDate_var
FROM test_cte;
-- End of second SELECT statement.
ELSE
date_a_var := NULL;
lastName_var := NULL;
firstName_var := NULL;
birthDate_var := NULL;
END IF;
It won't work because the test_cte only exists for the one statement and when you finish the statement's final SELECT statement then it no longer exists for the subsequent statements. (However, you do not use the sub-query factoring clause [a.k.a. CTE] in the SELECT for that statement so it is not clear why you need the WITH clause.)
Instead of trying to use COUNT, just get the data and handle the NO_DATA_FOUND exception if it occurs (also, from Oracle 12, you don't need to use RANK and can use FETCH FIRST ROW WITH TIES instead):
DECLARE
date_a_var test_table.date_a%TYPE;
lastName_var test_table.lastname%TYPE;
firstName_var test_table.firstname%TYPE;
birthDate_var test_table.birthdate%TYPE;
BEGIN
BEGIN
SELECT date_a,
lastName,
firstName,
birthDate
INTO date_a_var,
lastName_var,
firstName_var,
birthDate_var
FROM test_table a
join test_table b ON b.id = a.bid
ORDER BY date_a DESC
FETCH FIRST ROW WITH TIES;
EXCEPTION
WHEN NO_DATA_FOUND THEN
date_a_var := NULL;
lastName_var := NULL;
firstName_var := NULL;
birthDate_var := NULL;
END;
-- Continue processing
END;
(Note: You may also get a TOO_MANY_ROWS exception if there are duplicate dates. Either use FETCH FIRST ROW ONLY or, before Oracle 12, the ROW_NUMBER analytic function.)