Oracle 21c

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ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS';
CREATE TABLE table1 (ID, TEXT) AS
SELECT 1, 'It is %1 today with a %2 sky.' FROM DUAL UNION ALL
SELECT 2, 'It is %1 today with %2 and chances of %3.' FROM DUAL UNION ALL
SELECT 3, 'I just %1 have a %2 that %3 understand. We %4 need %5 to %6 on.' FROM DUAL;
3 rows affected

CREATE TABLE Table2 (ID, VALS) AS
SELECT 1, 'sunny/bright blue' FROM DUAL UNION ALL
SELECT 2, 'rainy/severe thunder storms/flooding' FROM DUAL UNION ALL
SELECT 3, 'might/problem/you''ll/all/somebody/lean' FROM DUAL UNION ALL
SELECT 1, 'rainy/gloomy' FROM DUAL;
4 rows affected

WITH bounds (id, v, b1, b2, b3, b4, b5, b6, b7, b8, b9) AS (
  SELECT id,
         vals,
         INSTR(vals, '/', 1, 1),
         INSTR(vals, '/', 1, 2),
         INSTR(vals, '/', 1, 3),
         INSTR(vals, '/', 1, 4),
         INSTR(vals, '/', 1, 5),
         INSTR(vals, '/', 1, 6),
         INSTR(vals, '/', 1, 7),
         INSTR(vals, '/', 1, 8),
         INSTR(vals, '/', 1, 9)
  FROM   table2
),
terms (id, t1, t2, t3, t4, t5, t6, t7, t8, t9, t10) AS (
  SELECT id,
         CASE
         WHEN b1 = 0 THEN v
         ELSE SUBSTR(v, 1, b1 - 1)
         END,
         CASE
         WHEN b2 = 0 AND b1 > 0 THEN SUBSTR(v, b1 + 1)
         WHEN b2 > 0 AND b1 > 0 THEN SUBSTR(v, b1 + 1, b2 - b1 - 1)
         END,
         CASE
         WHEN b3 = 0 AND b2 > 0 THEN SUBSTR(v, b2 + 1)
         WHEN b3 > 0 AND b2 > 0 THEN SUBSTR(v, b2 + 1, b3 - b2 - 1)
         END,
         CASE
         WHEN b4 = 0 AND b3 > 0 THEN SUBSTR(v, b3 + 1)
         WHEN b4 > 0 AND b3 > 0 THEN SUBSTR(v, b3 + 1, b4 - b3 - 1)
         END,
         CASE
         WHEN b5 = 0 AND b4 > 0 THEN SUBSTR(v, b4 + 1)
         WHEN b5 > 0 AND b4 > 0 THEN SUBSTR(v, b4 + 1, b5 - b4 - 1)
         END,
         CASE
         WHEN b6 = 0 AND b5 > 0 THEN SUBSTR(v, b5 + 1)
         WHEN b6 > 0 AND b5 > 0 THEN SUBSTR(v, b5 + 1, b6 - b5 - 1)
         END,
         CASE
         WHEN b7 = 0 AND b6 > 0 THEN SUBSTR(v, b6 + 1)
         WHEN b7 > 0 AND b6 > 0 THEN SUBSTR(v, b6 + 1, b7 - b6 - 1)
         END,
         CASE
         WHEN b8 = 0 AND b7 > 0 THEN SUBSTR(v, b7 + 1)
         WHEN b8 > 0 AND b7 > 0 THEN SUBSTR(v, b7 + 1, b8 - b7 - 1)
         END,
         CASE
         WHEN b9 = 0 AND b8 > 0 THEN SUBSTR(v, b8 + 1)
         WHEN b9 > 0 AND b8 > 0 THEN SUBSTR(v, b8 + 1, b9 - b8 - 1)
         END,
         CASE
         WHEN b9 > 0 THEN SUBSTR(v, b9 + 1)
         END
  FROM   bounds
)
SELECT t1.id,
       REPLACE(
         REPLACE(
           REPLACE(
             REPLACE(
               REPLACE(
                 REPLACE(
                   REPLACE(
                     REPLACE(
                       REPLACE(
                         REPLACE(text, '%10', t10),
                         '%9', t9
                       ),
                       '%8', t8
                     ),
                     '%7', t7
                   ),
                   '%6', t6
                 ),
                 '%5', t5
               ),
               '%4', t4
             ),
             '%3', t3
           ),
           '%2', t2
         ),
         '%1', t1
       ) AS replaced
FROM   table1 t1
       INNER JOIN terms t
       ON t1.id = t.id


ID
REPLACED


1
It is sunny today with a bright blue sky.

2
It is rainy today with severe thunder storms and chances of flooding.

3
I just might have a problem that you'll understand. We all need somebody to lean on.

1
It is rainy today with a gloomy sky.
ID	REPLACED
1	It is sunny today with a bright blue sky.
2	It is rainy today with severe thunder storms and chances of flooding.
3	I just might have a problem that you'll understand. We all need somebody to lean on.
1	It is rainy today with a gloomy sky.