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Re: [IndexedDB] Passing an empty array to IDBDatabase.transaction

From: Jonas Sicking <jonas@sicking.cc>
Date: Fri, 7 Oct 2011 14:14:18 -0700
Message-ID: <CA+c2ei8+pDbKeULwq0Budmg6mV+0q040OYvGrOxaZ_-xi44c9A@mail.gmail.com>
To: Israel Hilerio <israelh@microsoft.com>
Cc: Webapps WG <public-webapps@w3.org>
On Fri, Oct 7, 2011 at 11:51 AM, Israel Hilerio <israelh@microsoft.com> wrote:
> On Thursday, October 06, 2011 5:44 PM, Jonas Sicking wrote:
>> Hi All,
>>
>> In both the Firefox and the Chrome implementation you can pass an empty
>> array to IDBDatabase.transaction in order to create a transaction which has
>> a scope that covers all objectStores in the database. I.e. you can do
>> something like:
>>
>> trans = db.transaction([]);
>> trans.objectStore(<any objectstore here>);
>>
>> (Note that this is *not* a dynamic scoped transaction, it's still a static scope
>> that covers the whole database).
>>
>> In other words, these implementations treat the following two lines as
>> equivalent:
>>
>> trans = db.transaction([]);
>> trans = db.transaction(db.objectStoreNames);
>>
>> This, however, is not specified behavior. According to the spec as it is now
>> the transaction should be created with an empty scope.
>>
>> I suspect both Mozilla and Google implemented it this way because we had
>> discussions about this syntax on the list. However apparently this syntax
>> never made it into the spec. I don't recall why.
>>
>> I'm personally not a big fan of this syntax. My concern is that it makes it
>> easier to create a widely scoped transaction which has less ability to run in
>> parallel with other transactions, than to create a transaction with as narrow
>> scope as possible. And passing db.objectStoreNames is always possible.
>>
>> What do people think we should do? Should we add this behavior to the
>> spec? Or are implementations willing to remove it?
>>
>> / Jonas
>>
>
> Our implementation interprets the empty array as an empty scope.  We allow the transaction to be created but we throw a NOT_FOUND_ERR when trying to access any object stores.
> I vote for not having this behavior :-).

I'm fine with this, but I'd like to hear from Google too.

/ Jonas
Received on Friday, 7 October 2011 21:15:16 GMT

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