从条件的元组列表中选择值

Select value from list of tuples where condition(从条件的元组列表中选择值)

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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