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sqlite> select * from projects;
code client_id title start_date due_date
---------- ------------------------ --------------- ---------- ----------
ACME01 501 Ordering system 20030401 20031231
PREM3K 503 Thing 3000 20031201 20040430
PREM4K 503 Thing 4000 20031201 20040731
PREM5K 503 Thing 5000 20031201 20041031
ABCCONS 502 Ongoing consult 20030601
sqlite> select code , ifnull(due_date, 'ongoing')
...> from projects;
code ifnull(due_date, 'ongoin
---------- ------------------------
ACME01 20031231
PREM3K 20040430
PREM4K 20040731
PREM5K 20041031
ABCCONS ongoing
('' 위 예제를 봐서는 확실히 모르겠네요..^^;
IFNULL 펑션은 왜 사용하는겁니까??
null 값에 문자값을 넣기위한??? 용도? 답변 부탁드릴게요^^;;;
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