我有一个问题与SQL查询。在这种情况下,我需要得到其最后的历史活动是14天前的用户,但我的历史是空的,我怎么可以这样做:如果电子邮件历史记录为空上期14天,选择没有电子邮件历史SQL查询选择列表是否为空
SELECT st.id, st.firstName, st.lastName, st.email, st.lastLogin, st.phone, st.gender, sa.title,bra.Title as brand, ss.SaleDate, teh.sDate, sa.imageUrl, sa.guid, st.mallId, sa.id saleId
FROM dbo.Users st
INNER JOIN KEY_SalesToUsers ss ON (st.ID=ss.userID)
INNER JOIN Sales sa ON (sa.ID=ss.SaleID)
INNER JOIN Brands bra ON (sa.BrandID=bra.ID)
INNER JOIN dbo.UserEmailHistory teh ON st.id = teh.userId
WHERE CONVERT(date,DATEADD(day,1,ss.SaleDate))= CONVERT(date,getdate())
AND teh.sDate >= dateadd(dd,-14,getdate())
AND teh.sDate <= dateadd(dd,-13,getdate())
AND sDate <= dateadd(dd,-1,getdate())
ORDER BY ss.SaleDate DESC
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