Thanks Nick. So can you confirm costs are:
1.) For a projection query, cost is a single read for the entire query
regardless of number of results returned (and same under the new Datastore
pricing)
2.) For a projection query with distinct option, cost is 1 read + 1 read
per entity retrieved
3.) For normal queries ("SELECT * FROM ... " in GQL) under the new (from
July) Datastore pricing, cost is 1 read per entity
Are there drawbacks to the suggestion made by the poster of that link you
specified, in achieving a "SELECT * " at projection query cost, by adding
in a dummy property to the entity kind and then doing a projection query on
the remaining properties? (I suppose the obvious drawback being you'd need
an index for every property)
Thanks,
Alex
On Thursday, April 7, 2016 at 12:31:22 AM UTC+1, Nick (Cloud Platform
Support) wrote:
>
> Hi Alex,
>
> I believe this old App Engine Groups thread
> <https://groups.google.com/forum/#!msg/google-appengine/iL9ci30WSxU/0vLuvv8fAwAJ>
>
> answers your question adequately. Let me know if you have any questions
> after reading.
>
> Cheers,
>
> Nick
> Cloud Platform Community Support
>
> On Wednesday, April 6, 2016 at 10:12:15 AM UTC-4, Alex Kerr wrote:
>>
>> Hi,
>>
>> Can anyone clarify the cost of projection queries please? (both in
>> operations and financially)
>>
>> Datastore pricing page at:
>> https://cloud.google.com/datastore/docs/pricing says a regular query (is
>> that "SELECT * " ?) is 1 read + 1 read per entity retrieved. I get that,
>> but then projection queries are just "1 read" - which implies a cost of 1
>> read total regardless of the number of results returned and the number of
>> properties projected - that can't be right?
>>
>> Also I note the new pricing section from July but still not clear on
>> projection query cost!
>>
>> Many thanks
>> Alex
>>
>
--
You received this message because you are subscribed to the Google Groups
"Google App Engine" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to google-appengine+unsubscr...@googlegroups.com.
To post to this group, send email to google-appengine@googlegroups.com.
Visit this group at https://groups.google.com/group/google-appengine.
To view this discussion on the web visit
https://groups.google.com/d/msgid/google-appengine/00338ff3-2b30-44fa-89e1-8fba890e9bad%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
