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5. MySQL 拥有服务器资源友好质询的大型UPDATE 40Krow
原标题:MySQL mass UPDATE 40K rows with server resource friendly query

我有40千瓦的牢房,我必须像现在这样提出最新的问题:

UPDATE table1 
 SET column1= very long value 1... , column2= normal lenght value 1a 
WHERE pid = 123  and column3= ccc ;

页: 1

页: 1

......并想利用我的舱盘问,什么是更方便的服务器资源。

我想用的是:

UPDATE table1 
   CASE pid
    WHEN  123  THEN  very long value 1...  
    WHEN  124  THEN  very long value 2...   
    WHEN  543  THEN  very long value 4...   
    ...
    WHEN pid= 34532  THEN  very long value 5... 
    ELSE column1 
   END,
   column2= 
   CASE pid
    WHEN  123  THEN  normal lenght value 1a 
    WHEN  124  THEN  normal lenght value 2a 
    WHEN  543  THEN  normal lenght value 4a 
    ...
    WHEN pid= 34532  THEN  normal lenght value 5a 
    ELSE column2 
   END
WHERE pid IN ( 123 , 124 , 543 , ..., 34532 ) AND column3= ccc ;

我的问题是:有多少行能够更新<>/strong>,以这种方式在<中更新?

是否有其他服务器资源友好方法更新这40K浏览器?

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