Size of int in datastore

[Ashley Finney]

Hi all,

If the size of int is machine dependant, how many bytes are used when int is specified as a datastore field?

Will this change depending on the machine that stored the entity?  Or are int fields stored as size independent type?

Specifically I'm using Go if that matters.

Many thanks,

Ash.

[Alex Martelli]

In as much as protocol buffers are used in the underlying, #bytes depend on the exact value of the integer -- see https://developers.google.com/protocol-buffers/docs/encoding .

Alex

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[Jeff Schnitzer]

GAE/Java stores all integer numbers as 64 bit protobuf values. I presume all other runtimes do the same, otherwise there would be compatibility problems when reading from the datastore.

Jeff

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[Alex Martelli]

On Tue, Mar 3, 2015 at 10:09 AM, Jeff Schnitzer <je...@infohazard.org> wrote:

GAE/Java stores all integer numbers as 64 bit protobuf values. I presume all other

That's what is seen at the application-programming interface layer.  What's actually *stored* may take a different number of bytes, as per protobuf "wire"-level layouts.

runtimes do the same, otherwise there would be compatibility problems when reading from the datastore.

Yes, the RPCs to/from the datastore are uniform and don't vary with the application programming language (so, what you can store into, and retrieve from, an "integer property", is uniformly a 64-bit signed integer value).  That does not necessarily mean it will take the backend exactly 8 bytes to store it ("how many bytes are used" as it's stored).

Alex

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[Layo]

Hi Ashley,

Cloud Datastore uses 8 bytes to store signed integers, this independent from the machine. More info about Datastore types.