select substring(CONVERT(varchar,getdate(),21),1,7) + '-01' m_star,dateadd(day,-1,cast(substring(CONVERT(varchar,getdate(),21),1,5) + cast(cast(substring(CONVERT(varchar,getdate(),21),6,2) as int) + 1 as varchar) + '-01' as datetime)) as m_end
select
cast(cast(year(getdate())as char(4))+'/'+cast(month(getdate()) as char(2))+'/01' as datetime)as firstDate,
dateadd(d,-1,cast(cast(year(getdate())as char(4))+'/'+cast(month(dateadd(m,1, getdate())) as char(2))+'/01' as datetime)) as lastDate
select 月初=convert(varchar(10),cast(cast(datepart(yyyy,getdate()) as varchar)+'-'+cast(datepart(mm,getdate()) as varchar)+'-01' as datetime),120),月末=convert(varchar(10),dateadd(mm,1,cast(cast(datepart(yyyy,getdate()) as varchar)+'-'+cast(datepart(mm,getdate()) as varchar)+'-01' as datetime))-1,120)