本文介绍了从条件的元组列表中选择值的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着跟版网的小编来一起学习吧！
问题描述
我有一个元组列表.每个元组有 5 个元素(对应 5 个数据库列)，我想做一个查询
I have a list of tuples. Every tuple has 5 elements (corresponding to 5 database columns) and I'd like to make a query
select attribute1 from mylist where attribute2 = something
例如
personAge = select age from mylist where person_id = 10
是否可以通过某种方式查询元组列表?
Is it possible to query the list of tuples in some way?
推荐答案
如果你有 命名元组你可以这样做:
If you have named tuples you can do this:
results = [t.age for t in mylist if t.person_id == 10]
否则使用索引:
results = [t[1] for t in mylist if t[0] == 10]
或者按照 Nate 的回答使用元组解包.请注意，您不必为解包的每件物品指定一个有意义的名称.您可以执行 (person_id, age, _, _, _, _) 来解压缩六项元组.
Or use tuple unpacking as per Nate's answer. Note that you don't have to give a meaningful name to every item you unpack. You can do (person_id, age, _, _, _, _) to unpack a six item tuple.
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