我想要做的序列化列的简单查询，你是怎么做到这一点？

 连载：我的code，阵列


1.9.3p125：026＆GT; MyModel.find（104）。我的code
  为MyModel负载（0.6ms）选择`mymodels`。* FROM`mymodels` WHERE`mymodels`.`id` = 104 LIMIT 1
 =＆GT; [43565个，43402]
1.9.3p125：027＆GT; MyModel.find_all_by_my code（[43402]）
  为MyModel负荷（为0.7m​​s）选择`mymodels`。* FROM`mymodels` WHERE`mymodels`.`my code` ='[43402]
 =＆GT; []
1.9.3p125：028＆GT; MyModel.find_all_by_my code（43402）
  为MyModel负载（1.2ms的）选择`mymodels`。* FROM`mymodels` WHERE`mymodels`.`my code` = 43402
 =＆GT; []
1.9.3p125：029＆GT; MyModel.find_all_by_my code（[43565个，43402]）
  为MyModel负载（1.1ms）选择`mymodels`。* FROM`mymodels` WHERE`mymodels`.`my code` IN（43565个，43402）
 =＆GT; []
 

解决方案

基本上，你不能。 #serialize的缺点是，你绕过你的数据库的原生抽象。你是pretty的很多限制在加载和保存数据。

这是说，一个非常好的方式减慢你的应用程序如蜗牛可能是：

  MyModel.all.select {| M | m.my code.include？ 43402}
 

这个故事告诉我们：不要使用#serialize您需要查询上的任何数据。

I'm trying to do a simple query of a serialized column, how do you do this?

serialize :mycode, Array


1.9.3p125 :026 > MyModel.find(104).mycode
  MyModel Load (0.6ms)  SELECT `mymodels`.* FROM `mymodels` WHERE `mymodels`.`id` = 104 LIMIT 1
 => [43565, 43402] 
1.9.3p125 :027 > MyModel.find_all_by_mycode("[43402]")
  MyModel Load (0.7ms)  SELECT `mymodels`.* FROM `mymodels` WHERE `mymodels`.`mycode` = '[43402]'
 => [] 
1.9.3p125 :028 > MyModel.find_all_by_mycode(43402)
  MyModel Load (1.2ms)  SELECT `mymodels`.* FROM `mymodels` WHERE `mymodels`.`mycode` = 43402
 => [] 
1.9.3p125 :029 > MyModel.find_all_by_mycode([43565, 43402])
  MyModel Load (1.1ms)  SELECT `mymodels`.* FROM `mymodels` WHERE `mymodels`.`mycode` IN (43565, 43402)
 => [] 

Basically, you can't. The downside of #serialize is that you're bypassing your database's native abstractions. You're pretty much limited to loading and saving the data.

That said, one very good way to slow your application to a crawl could be:

MyModel.all.select { |m| m.mycode.include? 43402 }

Moral of the story: don't use #serialize for any data you need to query on.