select in a loop in oracle sql? - sql

Question

My stored procedure is used for getting string values of ids separate by ',' from a string contains names in table AUTH_GROUPS.
for example:
id name
1 role_1
2 role_2
3 role_3
the input is: 'role_1,role_2,role_3'
the output is: '1,2,3'
CREATE OR REPLACE PROCEDURE PROCEDURE1(P_ERROR_MSG OUT VARCHAR2, P_ROLE_STRING IN VARCHAR2 ) AS
BEGIN
DECLARE
lvOutPut VARCHAR2(2000);
vId varchar2(1000);
BEGIN
lvOutPut := '';
FOR i IN
(SELECT trim(regexp_substr(P_ROLE_STRING, '[^,]+', 1, LEVEL)) l
FROM dual
CONNECT BY LEVEL <= regexp_count(P_ROLE_STRING, ',')+1
)
LOOP
select id into vId from AUTH_GROUPS where NAME = i; --this line got error 'expression is of wrong type'
lvOutPut := lvOutPut || vId || ',';
END LOOP;
P_ERROR_MSG := lvOutPut;
P_ERROR_MSG := substr(P_ERROR_MSG, 1, LENGTH(P_ERROR_MSG) - 1);
END;
END PROCEDURE1;
But it has an error in the line that I commented. I tried i.1 or i.value but still got errors.

Answer 1

You need to use the actual column name. i is loop handle name.
....
BEGIN
lvOutPut := '';
FOR i IN
(SELECT trim(regexp_substr(P_ROLE_STRING, '[^,]+', 1, LEVEL)) l -- this is column name to be used inside the loop
FROM dual
CONNECT BY LEVEL <= regexp_count(P_ROLE_STRING, ',')+1
)
LOOP
select id into vId from AUTH_GROUPS where NAME = i.l; -- change here
...

Answer 2

/* Formatted on 6/23/2020 2:08:34 PM (QP5 v5.354) */
CREATE OR REPLACE PROCEDURE PROCEDURE1 (P_ERROR_MSG OUT VARCHAR2,
P_ROLE_STRING IN VARCHAR2)
AS
BEGIN
DECLARE
lvOutPut VARCHAR2 (2000);
vId VARCHAR2 (1000);
BEGIN
lvOutPut := '';
FOR i IN ( SELECT TRIM (REGEXP_SUBSTR (P_ROLE_STRING,
'[^,]+',
1,
LEVEL)) l
FROM DUAL
CONNECT BY LEVEL <= REGEXP_COUNT (P_ROLE_STRING, ',') + 1)
LOOP
SELECT id
INTO vId
FROM AUTH_GROUPS
WHERE NAME = i.l; --this line got error 'expression is of wrong type'
lvOutPut := lvOutPut || vId || ',';
END LOOP;
P_ERROR_MSG := lvOutPut;
P_ERROR_MSG := SUBSTR (P_ERROR_MSG, 1, LENGTH (P_ERROR_MSG) - 1);
END;
END PROCEDURE1;