mysql怎麼判斷字段為空
釋出時間:2020-06-08 17:17:02
來源:PHP中文網
閱讀:186
作者:三月
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這裡提供了5種方法進行查詢:
isnull()select * from users where email = 'xxxx' and isnull(deletedAt)
is nullselect * from users where email = 'xxxx' and deletedAt is null
is not nullselect * from users where email = 'xxxx' and deletedAt is not null
!isnull()select * from users where email = 'xxxx' and !isnull(deletedAt)
select * from users where email = 'xxxx' and not isnull(deletedAt)
isfull
當查詢條件為 null,用指定字元替代select name, isfull(gender,'未知') as gender from users where email = 'xxxx'
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