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SELECT REGEXP_SUBSTR('{AB}{C}{DEF}{HI{JKL}}', '{([^{}]+)}', 1, level, NULL, 1) AS str
FROM dual
CONNECT BY LEVEL <= REGEXP_COUNT('{AB}{C}{DEF}{HI{JKL}}', '{(.*?)}');
| STR |
|---|
| AB |
| C |
| DEF |
| JKL |