「Oracle入門」null判定方法を纏める
判定方法下記
1.decode関数 SELECT DECODE(USERNAME, NULL, 0, 1) AS NVLFLG FROM USERINFOTBL 2.case条件式 SELECT CASE WHEN USER_NAME IS NULL THEN 0 ELSE 1 END AS NVLFLG FROM USERINFOTBL 3.NUL2関数 SELECT NVL2(USER_NAME, 1, 0) AS NVLFLG FROM USERINFOTBL