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'
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.
You don't need to query to get an entity by key at all - you can simply fetch the entity by its key. In Python, you can do this with MyModel.get_by_key_name('_1'). This is 3 to 5 times faster than Adam's suggestion of using a query.