Oracle 21c

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ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS';
create table pod_label (
    name varchar2(256),
    key varchar2(256),
    value varchar2(256)
);
create table service_selector (
    name varchar2(256),
    key varchar2(256),
    value varchar2(256)
);
BEGIN
insert into pod_label (name, key, value) values ('p1', 'l1', '1');
insert into pod_label (name, key, value) values ('p1', 'l2', '2');
insert into pod_label (name, key, value) values ('p1', 'l3', '3');
insert into pod_label (name, key, value) values ('p2', 'l1', '1');
insert into pod_label (name, key, value) values ('p3', 'l1', 'N/A');
insert into service_selector (name, key, value) values ('s1', 'l1', '1');
insert into service_selector (name, key, value) values ('s1', 'l2', '2');
END;
/
1 rows affected

CREATE TYPE key_value_pair AS OBJECT(
  key   VARCHAR2(256),
  value VARCHAR2(256)
);
CREATE TYPE key_value_list AS TABLE OF key_value_pair;
SELECT name, key, value
FROM   (
  SELECT name,
         key,
         value,
         CAST(
           COLLECT(key_value_pair(key, value)) OVER (PARTITION BY name)
           AS key_value_list
         ) AS kvs
  FROM   pod_label
) pl
WHERE  EXISTS(
         SELECT 1
         FROM   service_selector ss
         GROUP BY name
         HAVING CAST(
                  COLLECT(key_value_pair(ss.key, ss.value))
                  AS key_value_list
                ) SUBMULTISET OF pl.kvs
       );


NAME
KEY
VALUE


p1
l1
1

p1
l2
2

p1
l3
3