半年之前
where 日期 between '${dateinmonth(monthdelta(today(),-5),1)}' and '${dateinmonth(today(),-1)}'
未来半年
where 日期 between '${dateinmonth(today(),1)}' and '${dateinmonth(monthdelta(today(),5),-1)}'
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半年之前
where 日期 between dateadd(m,-5,getdate())-day(getdate())+1 and dateadd(m,1,getdate())-day(getdate())
未来半年
where 日期 between dateadd(d,-day(getdate())+1,getdate()) and dateadd(m,6,getdate())-day(getdate())