1.mysql排名自定义实现rank
SELECT
tmp.id,tmp.custoemr_name,tmp.score,
-- 顺序一直在变大
@j:
=@j+1 AS j,
-- 顺序排序,有并列情况
@n:
=(
CASE WHEN @pre_score=tmp.score
THEN @n ELSE @n + 1 END)
AS n,
-- 只有在前后二次排序值不同时才会使用顺序号
@k:
=(
CASE WHEN @pre_score=tmp.score
THEN @k ELSE @j END)
AS rank,
@pre_score:
=tmp.score
AS pre_score
FROM
(
-- 成绩排序
SELECT * FROM ldf_customer
ORDER BY score
DESC
) tmp,
-- @k 表示最终的排名(相同值时序号相同)
-- @j 表示顺序排名
-- @pre_score上一次排序值
(
SELECT @k :
=0,
@j:
=0,
@n:
=0,
@pre_score:
=0) sdcore
原著:http://www.cnblogs.com/bjwylpx/p/5345162.html
转载于:https://www.cnblogs.com/lidaofei1991/articles/6594095.html