select case(
when MAX(col1) > MAX(col2) then 'col1大'
when MAX(col1) < MAX(col2) then 'col2大'
else '相等' end)as COL1,
case(
when MIN(col1) < MIN(col2) then 'col1小'
when MIN(col1) > MIN(col2) then 'col2小'
else '相等' end)as COL2,
case(
when avg(col1) < avg(col2) then 'col1品均小与col2'
when avg(col1) > avg(col2) then 'col2品均小与col1'
else '相等' end)as COL3
from table1