I have been working on writing serializable structure for remote filtering of values on the distributed hash table OpenDHT. This structure is called Query.

What’s done

The implementation of the base design with other changes have been made. You can see evolution on the matter here;

Changes allow to create a Query with a SQL-ish statement like the following

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Query q("SELECT * WHERE id=5");

You can then use this query like so

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get(hash, getcb, donecb, filter, "SELECT * WHERE id=5");

I verified the working state of the code with the dhtnode. I have also done some tests using our python benchmark scripts.

What’s next

• Value pagination;
• Optimization of put operations with query for ids before put, hence avoiding potential useless traffic.

Thoughts

The Query is the key part for optimizing my initial work on data persistence on the DHT. It will enhance the DHT on more than one aspects. I have to point out it would not have been possible to do that before our major refactoring we introduced in 0.6.0.