如何使用实体键在GQL中进行查询 [英] How do I query in GQL using the entity key

问题描述

在查看器中，第一列（Id / Name）显示为 name = _1 ，在详细视图中显示为

 解码实体密钥：程序：name = _1 
实体密钥：agtzcG9 ................... 
  

此查询不起作用：

  SELECT * FROM Program name ='_1'
  

解决方案

您可以使用实体的密钥来检索它：

  SELECT * FROM Program where __key__ = KEY（'agtzcG9 ......... ..........'）
  

而且，您应该可以使用查询名称类似：

  SELECT * FROM程序其中__key__ = KEY（程序，'_1'）
  

请注意，这不是您想在AppEngine应用程序中执行的操作N;正如尼克在评论中所指出的那样，这是对时间的巨大浪费。真的，这个例子只是向你展示如何在管理控制台中通过Key进行查询。

How do I write a query against the entity key using GQL in the Google App Engine Data Viewer ?

In the viewer, the first column (Id/Name) displays as name=_1, in the detail view it shows the key as

Decoded entity key: Programme: name=_1
Entity key: agtzcG9................... 

This query does not work:

SELECT * FROM Programme where name = '_1'

解决方案

You can use the entity's key to retrieve it:

SELECT * FROM Programme where __key__ = KEY('agtzcG9...................')

And, you should be able to query using the name similarly:

SELECT * FROM Programme where __key__ = KEY(Programme, '_1')

Note that this is not something that you would want to do in your AppEngine application; as Nick notes in his comment, it is a huge waste of time. Really, this example is only good to show you how to query by Key in the Admin console.

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