Možností je více. Viz Rozdělení řetězců oddělených čárkami v tabulce v Oracle .
Pomocí REGEXP_SUBSTR:
SQL> WITH sample_data AS(
2 SELECT 10001 ID, 'A,B,C' str FROM dual UNION ALL
3 SELECT 10002 ID, 'D,E,F' str FROM dual UNION ALL
4 SELECT 10003 ID, 'C,E,G' str FROM dual
5 )
6 -- end of sample_data mimicking real table
7 SELECT distinct id, trim(regexp_substr(str, '[^,]+', 1, LEVEL)) str
8 FROM sample_data
9 CONNECT BY LEVEL <= regexp_count(str, ',')+1
10 ORDER BY ID
11 /
ID STR
---------- -----
10001 A
10001 B
10001 C
10002 D
10002 E
10002 F
10003 C
10003 E
10003 G
9 rows selected.
SQL>
Pomocí XMLTABLE:
SQL> WITH sample_data AS(
2 SELECT 10001 ID, 'A,B,C' str FROM dual UNION ALL
3 SELECT 10002 ID, 'D,E,F' str FROM dual UNION ALL
4 SELECT 10003 ID, 'C,E,G' str FROM dual
5 )
6 -- end of sample_data mimicking real table
7 SELECT id,
8 trim(COLUMN_VALUE) str
9 FROM sample_data,
10 xmltable(('"'
11 || REPLACE(str, ',', '","')
12 || '"'))
13 /
ID STR
---------- ---
10001 A
10001 B
10001 C
10002 D
10002 E
10002 F
10003 C
10003 E
10003 G
9 rows selected.