Oracle 18c

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CREATE TABLE test_data ( id, value ) AS
SELECT 1, '|2020/04/26|2020/05/02|2020/05/03|2020/05/10' FROM DUAL UNION ALL
SELECT 2, '|2020/06/01|2020/06/02' FROM DUAL
2 rows affected

SELECT id,
       x.*
FROM   test_data t
       CROSS JOIN
       XMLTABLE(
         ( LTRIM(
             REGEXP_REPLACE(
               t.value,
               '\|(\d{4}/\d{2}/\d{2})\|(\d{4}/\d{2}/\d{2})',
               ',<row><start>\1</start><end>\2</end></row>'
             ),
             ','
           )
         )
         COLUMNS
           start_date DATE PATH '/row/start',
           end_date   DATE PATH '/row/end'
       ) x


ID
START_DATE
END_DATE


1
26-APR-20
02-MAY-20

1
03-MAY-20
10-MAY-20

2
01-JUN-20
02-JUN-20


SELECT REGEXP_SUBSTR ( value, '\|(\d{4}/\d{2}/\d{2})\|(\d{4}/\d{2}/\d{2})', 1, level, NULL, 1 ) as start_date,
       REGEXP_SUBSTR ( value, '\|(\d{4}/\d{2}/\d{2})\|(\d{4}/\d{2}/\d{2})', 1, level, NULL, 2 ) as end_date
FROM   (
  SELECT value
  FROM   test_data
  WHERE  ROWNUM = 1
)
CONNECT BY LEVEL <= REGEXP_COUNT( value, '\|(\d{4}/\d{2}/\d{2})\|(\d{4}/\d{2}/\d{2})' )


START_DATE
END_DATE


2020/04/26
2020/05/02

2020/05/03
2020/05/10