oracle关于时间段比较大小的问题,给个思路

select case when to_char(col_date,'HH24:mi:ss') >'12:00:00' then '后一个科室' else '前一个科室' end

to_date(to_char(Tbale1.date, 'yyyymmdd') || to_char(Tbale1.time, 'hh24miss'), 'yyyymmddhh24miss') >to_date(Table2.datetime, 'yyyymmddhh24miss')

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