| 물리명 | 논리명 | 타입 | 길이 |
|---|---|---|---|
| 유형 | type | 문자형 | 100 |
| 값 | value | 문자형 | 100 |
CREATE TABLE ex_null_empty ( type VARCHAR(100) NOT NULL, value VARCHAR(100) );
INSERT INTO ex_null_empty (type, value) VALUES ('NULL', NULL);
INSERT INTO ex_null_empty (type, value) VALUES ('빈 문자열', '');
-- 빈 값 SELECT * FROM ex_null_empty WHERE value IS NULL OR value = '' ; -- 빈 값 아님 SELECT * FROM ex_null_empty WHERE value IS NOT NULL AND value <> '' ;
-- 빈 값 SELECT * FROM ex_null_empty WHERE value IS NULL OR value = '' ; -- 빈 값 아님 SELECT * FROM ex_null_empty WHERE value IS NOT NULL AND value <> '' ;
-- 빈 값 SELECT * FROM ex_null_empty WHERE value IS NULL ; -- 빈 값 아님 SELECT * FROM ex_null_empty WHERE value IS NOT NULL ;
-- 빈 값 SELECT * FROM ex_null_empty WHERE value IS NULL OR value = '' ; -- 빈 값 아님 SELECT * FROM ex_null_empty WHERE value IS NOT NULL AND value <> '' ;