Oracle 18c

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CREATE TABLE table1 ( CODE, RATE1, type, MONTH ) AS
SELECT 'A', 0, 'Acc1', 201906 FROM DUAL UNION ALL
SELECT 'A', 0, 'Acc1', 201907 FROM DUAL UNION ALL
SELECT 'A', 0, 'Acc1', 201908 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc1', 201909 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc1', 201910 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc1', 201911 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc1', 201912 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc1', 202001 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc1', 202002 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc1', 202003 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc1', 202004 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc1', 202005 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc1', 202006 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc1', 202007 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc1', 202008 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc1', 202009 FROM DUAL UNION ALL

SELECT 'A', 0, 'Acc2', 201906 FROM DUAL UNION ALL
SELECT 'A', 0, 'Acc2', 201907 FROM DUAL UNION ALL
SELECT 'A', 0, 'Acc2', 201908 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc2', 201909 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc2', 201910 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc2', 201911 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc2', 201912 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc2', 202001 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc2', 202002 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc2', 202003 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc2', 202004 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc2', 202005 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc2', 202006 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc2', 202007 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc2', 202008 FROM DUAL UNION ALL
SELECT 'A', 1, 'Acc2', 202009 FROM DUAL;
32 rows affected

CREATE TABLE table2 ( CODE, RATE2, MONTH ) AS
SELECT 'A', 10, 202001 FROM DUAL UNION ALL
SELECT 'A', 10, 202002 FROM DUAL UNION ALL
SELECT 'A', 10, 202003 FROM DUAL UNION ALL
SELECT 'A', 10, 202004 FROM DUAL;
4 rows affected

SELECT code,
       rate1,
       rate2,
       type,
       first_month,
       last_month
FROM   (
  SELECT t1.code,
         t1.rate1,
         COALESCE( t2.rate2, 0 ) AS rate2,
         t1.type,
         t1.month
  FROM   table1 t1
         LEFT OUTER JOIN table2 t2
         ON ( t1.code = t2.code AND t1.month = t2.month )
)
MATCH_RECOGNIZE (
   PARTITION BY type
   ORDER BY month
   MEASURES
      FIRST( code ) AS code,
      FIRST( rate1 ) AS rate1,
      FIRST( rate2 ) AS rate2,
      FIRST( month ) AS first_month,
      LAST( month ) AS last_month
   ONE ROW PER MATCH
   PATTERN (FIRST_ROW SAME_RATES*)
   DEFINE
      SAME_RATES AS (    SAME_RATES.rate1 = PREV(SAME_RATES.rate1)
                     AND SAME_RATES.rate2 = PREV(SAME_RATES.rate2) )
)
ORDER BY type, first_month;


CODE
RATE1
RATE2
TYPE
FIRST_MONTH
LAST_MONTH


A
0
0
Acc1
201906
201908

A
1
0
Acc1
201909
201912

A
1
10
Acc1
202001
202004

A
1
0
Acc1
202005
202009

A
0
0
Acc2
201906
201908

A
1
0
Acc2
201909
201912

A
1
10
Acc2
202001
202004

A
1
0
Acc2
202005
202009
CODE	RATE1	RATE2	TYPE	FIRST_MONTH	LAST_MONTH
A	0	0	Acc1	201906	201908
A	1	0	Acc1	201909	201912
A	1	10	Acc1	202001	202004
A	1	0	Acc1	202005	202009
A	0	0	Acc2	201906	201908
A	1	0	Acc2	201909	201912
A	1	10	Acc2	202001	202004
A	1	0	Acc2	202005	202009