Size of index in case of exploding index

[Nash]

Hello folks,

The documentation here:
http://code.google.com/appengine/docs/datastore/queriesandindexes.html#Big_Entities_and_Exploding_Indexes

says that given a model thus:

class MyModel(db.Expando):
pass

and an instance thus:

e2 = MyModel()
e2.x = ['red', 'blue']
e2.y = [1, 2]
e2.put()

then the following index:

indexes:
- kind: MyModel
properties:
- name: x
- name: y

will generate 8 rows in the index table. Can anyone explain how?

I thought it would be 4 like this:
x, y
'red', 1
'red', 2
'blue', 1
'blue', 2

Also, in case of a repeating property:

indexes:
- kind: MyModel
properties:
- name: x
- name: x

will this also have 8 rows?

I'd love to hear your input

[Nash]

The topic is a misnomer, it should be Size of index in case of multi-
property attributes

On Sep 1, 7:46 pm, Nash <nasrul...@gmail.com> wrote:
> Hello folks,
>

> The documentation here:http://code.google.com/appengine/docs/datastore/queriesandindexes.htm...

[ryan]

hi nash! the extra four index rows come from the built-in single
property indexes. in this example, they'll need two index rows for x
and two for y. you're right, the docs don't fully describe this. i'll
update them. thanks for the nudge!

as for your repeated property index, yes, it will also have 8 index
rows, four for the built-in indexes for x and y and four for each (x,
x) permutation.

[Nash]

Great, thanks!