Question

首先，为可怕的标题道歉，我想不出更好的方式来表达我的问题。（随意建议更好的altnernatives）

基本上我有一个带有“count”列的表。我想将所有计数重置为零，除了具有最高值的10行。我希望它们重置为0。

如何在不编写多个查询的情况下实现此目的？

更新我现在的查询如下

UPDATE covers AS t1 
  LEFT JOIN (SELECT t.cover_id 
               FROM covers t 
               ORDER BY t.cover_views DESC 
               LIMIT 10) AS t2 ON t2.id = t.id
   SET cover_views = 0
   WHERE t2.id IS NULL

我收到错误#1054 - Unknown column 't2.id' in 'where clause' - 知道为什么？

我也尝试了以下相同的结果

UPDATE covers t1 
  LEFT JOIN (SELECT t.cover_id 
               FROM covers t 
               ORDER BY t.cover_views DESC 
               LIMIT 10) t2 ON t2.id = t.id
   SET t1.cover_views = 0
   WHERE t2.id IS NULL

Answer 1

使用：

UPDATE TABLE t1 
  LEFT JOIN (SELECT t.id 
               FROM TABLE t 
           ORDER BY t.id DESC 
              LIMIT 10) t2 ON t2.id = t1.id
   SET TABLE.count = 0
 WHERE t2.id IS NULL

Answer 2

尝试：

update <table> t 
left outer join 
(
select id from <table> order by <counter> desc limit 10
) c on c.id = t.id 
set 
 <counter> = 0
where 
 c.id is null;

Answer 3

您可以使用子查询：

update A set count = 0 where A.id not in 
(select id from A order by count desc limit 10)

MySQL UPDATE - 选择性更新

3 个答案: