Google App Engine - Datastore get_or_insert key_name confusion [英] Google App Engine - Datastore get_or_insert key_name confusion

问题描述

我对 get_or_insert（..）感到困惑。作为 key_name ，我应该传递什么？考虑下面的例子：

I am confused by get_or_insert(..). What should I pass as the key_name? Consider the following example:

class Person(db.model)
    name = db.StringProperty(required=True)

假设没有两个人可以拥有相同的名称。说我想要获得或插入一个名为 Peter 的新人，我的 get_or_insert 语句看起来像什么？

Assume that no two people can have the same name. Say I want to get or insert a new Person with name Peter, what would my get_or_insert statement look like?

干杯，

Pete

推荐答案

这里可能令人困惑的是，键不直接显示在你的模型声明中，所以 name = db .StringProperty 位不需要。 get_or_insert 将键名作为其第一个（必需）参数，因此您要查找的代码如下：

The possibly confusing thing here is that the key doesn't show up directly in your model declaration, so that name = db.StringProperty bit in your example isn't needed. get_or_insert takes the keyname as its first (required) argument, so you're looking for code like:

person = Person.get_or_insert('Peter')
# other interesting & useful code here...
# later, maybe we need to retrieve that key name from the object:
name = person.key().name()
assert(name == "Peter")

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