SUBQUERY에서의 IN, NOT IN
CREATE TABLE MAIN( SEQ NUMBER(10) , VAL VARCHAR2(10) ); CREATE TABLE MAIN( SEQ NUMBER(10) , VAL VARCHAR2(10) ); INSERT INTO MAIN VALUES ( 1, 'A' ); INSERT INTO MAIN VALUES ( 2, NULL); INSERT INTO MAIN VALUES ( 3, 'B'); INSERT INTO MAIN VALUES ( 4, 'C'); INSERT INTO SUB VALUES ( 1, 'A' ); INSERT INTO SUB VALUES ( 2, NULL); INSERT INTO SUB VALUES ( 3, 'B'); COMMIT; SELECT * FROM MAIN A WHERE A.VAL..