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CREATE TABLE example
(
uuid CHAR(36) CHECK (REGEXP_LIKE(uuid, '[0-9a-f]{8}-([0-9a-f]{4}-){3}[0-9a-f]{12}'))
);
INSERT INTO example VALUES ('123e4567-e89b-12d3-a456-426614174000');
1 rows affected
INSERT INTO example VALUES ('123e4567-e89b-12d3-a456-426614174z00'); --See Z
ORA-00933: SQL command not properly ended