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Re: Why not be multiEntry and array keyPath togather?

From: Joshua Bell <jsbell@google.com>
Date: Thu, 25 Apr 2013 10:14:39 -0700
Message-ID: <CAD649j5fsh_nZXi4OsrX+OG3qWA+37Rxgm+gJCCrgZhDwHPukg@mail.gmail.com>
To: Kyaw Tun <kyawtun@yathit.com>
Cc: "public-webapps@w3.org" <public-webapps@w3.org>
Some of us were just discussing this yesterday - it does seem reasonable
for the next iteration.

Can you file a bug at https://www.w3.org/ (product: WebAppsWG, component:
Indexed Database API) to track this?

Including scenario details such as you've done above would be great.


On Thu, Apr 25, 2013 at 7:09 AM, Kyaw Tun <kyawtun@yathit.com> wrote:

>  createIndex<http://www.w3.org/TR/IndexedDB/#widl-IDBObjectStore-createIndex-IDBIndex-DOMString-name-any-keyPath-IDBIndexParameters-optionalParameters>API specification state that "If keyPath is and Array and the multiEntry
> property in the optionalParameters is true, then a DOMException of type
> NotSupportedError must be thrown".
>
> I believe NotSupportedError is unnecessary. multiEntry is no different
> than non-multiEntry index value, except the reference value is repeated.
> This specification limit generalizes usage of composite index for key
> joining algorithm.
>
> Google appengine datastore also have have multiEntry (ListProperty<https://developers.google.com/appengine/docs/python/datastore/typesandpropertyclasses#ListProperty>).
> It has no special different in indexing, other than limiting number of
> entries<https://groups.google.com/forum/?fromgroups=#!topic/google-appengine/1fTct9AO1MY>and warning for possibility of explosive index.
>
> Composite index with multiEntry is very useful, like modelling graph data
> and many-to-many relationship. Currently query on such model are limited to
> single index.
>
> It is also very unlikely that web developer will use excessive indexing. I
> propose NotSupportedError left out of specification.
>
> Best regards,
> Kyaw
>
>
>
Received on Thursday, 25 April 2013 17:19:03 UTC

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