数据：

一、整体排名(3种)

-- 普通排名：从1开始，顺序往下排

set @rank =0;select     city ,    score,     @rank := @rank+1 rank from     cs order by     score desc;

-- 并列排名：相同的值是相同的排名,不用占空位

set @rank=0,@price=null;select cs.* , case when @price = score then @rank  when @price := score then @rank := @rank+1 end rank   from cs order by score desc; -- 当查询的score 值 = @price时，输出@rank, -- 当不等时，将score值赋给@price ，并输出@rank := @rank+1 -- 或者set @rank=0,@price=null;select a.city,a.score,a.rank from (select cs.*,@rank := if(@p=score,@rank,@rank+1) rank,@p := scorefrom cs order by score desc) a;

-- 并列排名：相同的值是相同的排名,需要占空位

set @rank=0,@price=null, @z=1;select a.city,a.score,a.rank from (select cs.*,@rank := if(@p=score,@rank,@z) rank,@p := score,@z :=@z+1from cs order by score desc) a;

二、分组后组内排名(3种)

-- 分组普通排名：顺序排名

set @rank=0,@c=null;select cs.city,cs.score,@rank := if(@c = city,@rank+1,1) rank,@c := cityfrom cs order by cs.city,cs.score;

-- 组内并列排名：相同的值是相同的排名,不需要占空位

set @rank=0,@c=null,@s=null;select cs.city,cs.score,@rank := if(@c=city,if(@s=score,@rank,@rank+1),1) rank ,@c := city,@s :=score from cs order by cs.city,cs.score;

-- 组内并列排名：相同的值是相同的排名,需要占空位

set @rank=0,@z=0,@c=null,@s=null;select cs.city,cs.score,@z := if(@c=city,@z+1,1),@rank := if(@c=city,if(@s=score,@rank,@z),1) rank,@c := city,@s :=score from cs order by cs.city,cs.score;

三、分组后取各组的前两名

-- 方法1：按照分组排名的三种方式，然后限定排名的值

set @rank=0,@z=0,@c=null,@s=null;select a.city,a.score,a.rank from (select cs.city city,cs.score score,@z := if(@c=city,@z+1,1),@rank := if(@c=city,if(@s=score,@rank,@z),1) rank,@c := city,@s :=score from cs order by cs.city,cs.score desc) awhere a.rank<=2;

-- 方法2：内部查询

SELECT * FROM cs cWHERE (    SELECT count(*) FROM cs    WHERE c.city=cs.city AND c.score2  ORDER BY city,score DESC;