例:
SELECT distinct REGEXP_SUBSTR('a,b,c,d,e', '[^,]+', 1, level) from dual connect by level <= regexp_count('a,b,c,d,e', ',') + 1
--(红色字体表示字段)
结果:
或:
SELECT distinct REGEXP_SUBSTR('a,b,c,d,e', '[^,]+', 1, level) from dual connect by level <= LENGTH('a,b,c,d,e')-LENGTH(REPLACE('a,b,c,d,e',',','')) + 1