[continuations]

- Secondary Index

- some way to store ordered records to speed up range query

- comparison & benchmarks of FoundationDB vs other distributed DB like TiDB, CockroachDB, ScyllaDB, etc

[ryanworl]

Those first two are pretty trivial. Keys are already stored in sorted order in a b-tree. Secondary indexing involves putting the indexed value to the left of the primary key in the key you write.

[continuations]

> Keys are already stored in sorted order in a b-tree

I thought FoundationDB stored data in a hash table. Didn't realize it uses a b-tree. Thanks for the clarification.

> Secondary indexing involves putting the indexed value to the left of the primary key in the key you write

By secondary index I meant having a sort order that's different from the primary key sort order.

[rbranson]

FoundationDB provides the building blocks. Secondary indexes can be built on top of the regular primary index. Transactions make it possible to maintain a consistent 2I using a K/V interface.