Feature request: async put/get

[Buggaboo]

This could be implemented and return as streams/futures, for huge data transfers, to not block the main thread.

I don't do huge data transfers, but I guess there are use cases where people do huge transfers, e.g. time series etc.

[vaind]

One thing to keep in mind, while I'm not against using streams/futures per se: there's already AsyncBox support in ObjectBox, providing fast asynchronous put (without a confirmation so can't be used as a future)

See also: #49

[Buggaboo]

Ah I get it.

[siyehua]

One thing to keep in mind, while I'm not against using streams/futures per se: there's already AsyncBox support in ObjectBox, providing fast asynchronous put (without a confirmation so can't be used as a future)

See also: #49

now is 2021.10 ， the objecBox only support put async, get is not support 😭

[westito]

There is 2022 and ObjectBox still not supports async queries...

[greenrobot]

@siyehua One could argue that there is little reason for an async get if the synchronous get has negligible cost. But sure, main thread and so on, so since this issue is closed for quite some time, please create a new issue for this if you still want to (to track interest).

@westito Try https://docs.objectbox.io/queries#query-results-stream to process query async.

@greenrobot-team The docs probably should mention async queries more prominently?

[westito]

Can we say that because of mmap, retrieving synchronously from the database is practically the same as retrieving directly from memory? In other words, there is not much benefit from the asynchronous operation. Moreover, its overhead is much higher.

[greenrobot]

@westito In case the data pages have been accessed before it's very likely that they are in memory; in practice I haven't seen a problem with synchronous get (like) ops in the last 15 years or so (ofc, there are special cases).

[greenrobot-team]

As mentioned it's possible to query.stream() query results (https://docs.objectbox.io/queries#query-results-stream), which is async. The other query methods (like findIds(); or any other box operations) can be wrapped with store.runInTransactionAsync (https://docs.objectbox.io/getting-started#asynchronous-operations) to make them async.