--回站车辆
select count(distinct dph) from wxd where jcrq>='20060101' and jcrq<='20060131'and dph in (select distinct dph  where jcrq>='20060201' and jcrq<='20060531')

{0EA068F5-DC59-416A-941C-B5A9CD3ADADC}


--总车辆数
select count(distinct dph) from wxd where jcrq>='20060101' and jcrq<='20060131'