CONNECT BY LEVEL

A condition that identifies the relationship between parent rows and child rows of the hierarchy

CREATE TABLE t (
rid NUMBER(12),
col1 VARCHAR2(30),
col2 VARCHAR2(300));

CREATE SEQUENCE seq_t_rid;

INSERT INTO t
SELECT seq_t_rid.NEXTVAL, dbms_crypto.randombytes(15), dbms_crypto.randombytes(150)
FROM DUAL
CONNECT BY LEVEL <= 1000;