Table : tbl_email_scheduler
這裏date_to_send = '2013-10-12' AND send_status = NULL
。 (在時間createing表我已經給SEND_STATUS默認NULL)查詢給出空的結果,因爲where子句
MySQL的:
SELECT
id,
to_users,
subject,
message,
product_id,
date_to_send,
send_status,
status,
createdate
FROM tbl_email_scheduler
WHERE date_to_send = '2013-10-12'
給我造成
但是,當我
SELECT
id,
to_users,
subject,
message,
product_id,
date_to_send,
send_status,
status,
createdate
FROM tbl_email_scheduler
WHERE date_to_send = '2013-10-12'
and send_status != 'Y'
它給我空的結果,爲什麼? 請回答。