select
convert(varchar(100), getdate(), 25) as 当前时间,
datename(weekday, convert(varchar(100), getdate(), 11)) as 星期,
case
when convert(varchar(100), getdate(), 14) < '12:00:00.000' then '0-12点'
when convert(varchar(100), getdate(), 14) >= '18:00:00.000' then '18-0点'
else '12-18点'
end as '当前时间段'