统计的sql 语句,同一个字段为不同值进行统计

select     sum(case status when 'high' then 1 else 0 end) intHigh ,sum(case status when 'middle' then 1 else 0 end) intMiddle,sum(case status when 'low' then 1 else 0 end) intLow      from tbl_tableName;