php - 根据给定的排名和顺序显示mysql记录

Question

我正在写一个查询，我应该根据给定的排名位置以及价格顺序和按站点名称分组来显示记录

shopdetails

id | productid | productname | sitename | siteid | site_priority | price | color
1     555          xyz          a          1          0            10      blue  
2     555          xyz          b          12         1            50      blue  
3     555          xyz          a          1          0            12      red  
4     555          xyz          c          3          4            9       red
5     555          xyz          e          15         5            19      blue
6     555          xyz          e          15         5            21      red
7     555          xyz          b          12         1            42      red 
8     555          xyz          c          3          4            56      blue

我必须满足的三个条件才能获得预期的输出条件

1. 如果 site_priority !=0 则将该记录放在该位置。说例如。如果 site_priority = 5 。将所有站点名称分组后显示该记录排在第五位
2. 如果 site_priority = 0 则显示记录价​​格 asc
3. 按站点名称对记录进行分组并按价格排序

最终预期输出

id | productid | productname | sitename | siteid | site_priority | price | color
  7     555          xyz           b        12           1            42    red   
  2     555          xyz           b        12           1            50    blue

############ the above two records are kept in the First Position since site_priority = 1 and ordered by price asc    
Now check for site_priority 2 is there if not show site_priority = 0 by price asc  ,
Now 2nd records would be

  1     555          xyz          a          1          0            10      blue 
  3     555          xyz          a          1          0            12      blue 

 Now check for site_priority 3 is there if not check for site_priority 0 ,
 is not then make the priority one level minus .
 move site_priority 4 to 3 , 5 to 4 .

  4     555          xyz          c          3          4            9       red
  8     555          xyz          c          3          4            56      blue
  5     555          xyz          e          15         5            19      blue
  6     555          xyz          e          15         5            21      red

有没有最好的方法来完成这个复杂的查询。

我厌倦了这样做，但它并没有像我预期的那样出现。

select 
    productid,
    productname,
    sitename,
    site_priority,
    price,
    colorname,
    (select 
            count(*)
        from
            shopdetails b
        where
            productid = 1250 and b.site_priority > a.site_priority order by price asc)+1  as rnk
from
    shopdetails a
where
    productid = 1250
having site_priority > 0
order by rnk

我的第一个条件很容易理解

sitename | priority
a            1
b            2  
c            3
d            0  
e            0
f            0
g            0
h            0
i            5



outpt

a  1 ==> position 1
b  2 ==> position 2
c  3 ==> position 3
d  0 ==> position 4
i  5 ==> position 5
e  0 ==> position 6
f  0 ==> position 7
g  0 ==> position 8
h  0 ==> position 9

Answer 1

这是一个有趣的问题。我不确定我是否正确理解了你，但这是我想出的(有点古怪)。不过，它与您的示例输出匹配。

SELECT * FROM test
ORDER BY CASE WHEN site_priority = 0 THEN (
    SELECT k.outp FROM (
        SELECT @rownum:= @rownum + 1 outp, t.site_priority outp2 FROM (
            SELECT DISTINCT site_priority FROM test ORDER BY site_priority ASC) t, 
            (SELECT @rownum := 0) r 
            WHERE t.site_priority != @rownum) k 
    WHERE k.outp != k.outp2 limit 1)
ELSE site_priority END, sitename, price;