Peter Dillinger
82794e0a4f
Summary: The new API in https://github.com/facebook/rocksdb/issues/13453 is awkward and precarious because of using RangePtr, which encodes optional keys using raw pointers to Slice. We could use `std::optional<Slice>` instead but that is unsatisfyingly a larger object with an inefficient size (typically 17 bytes). Here I introduce a custom optional Slice type, `OptSlice`, that is the same size as a Slice, and use it in a number of places to clean up code and make some public APIs easier to work with. This includes * `atomic_replace_range` (not yet released, OK to change) * `GetAllKeyVersions()` which gets a behavior change because of its unusual handling of empty keys. * `DeleteFilesInRanges()` * TODO in follow-up: `CompactRange()` Most of the diff is associated updates and refactorings. Also * Move some relevant things out of db.h to keep it as tidy as possible. Pull Request resolved: https://github.com/facebook/rocksdb/pull/13481 Test Plan: tests updated Reviewed By: hx235 Differential Revision: D71747774 Pulled By: pdillinger fbshipit-source-id: b4c8519608d119b8bceca9bb0fd778608f62a141
RocksDB: A Persistent Key-Value Store for Flash and RAM Storage
RocksDB is developed and maintained by Facebook Database Engineering Team. It is built on earlier work on LevelDB by Sanjay Ghemawat (sanjay@google.com) and Jeff Dean (jeff@google.com)
This code is a library that forms the core building block for a fast key-value server, especially suited for storing data on flash drives. It has a Log-Structured-Merge-Database (LSM) design with flexible tradeoffs between Write-Amplification-Factor (WAF), Read-Amplification-Factor (RAF) and Space-Amplification-Factor (SAF). It has multi-threaded compactions, making it especially suitable for storing multiple terabytes of data in a single database.
Start with example usage here: https://github.com/facebook/rocksdb/tree/main/examples
See the github wiki for more explanation.
The public interface is in include/. Callers should not include or
rely on the details of any other header files in this package. Those
internal APIs may be changed without warning.
Questions and discussions are welcome on the RocksDB Developers Public Facebook group and email list on Google Groups.
License
RocksDB is dual-licensed under both the GPLv2 (found in the COPYING file in the root directory) and Apache 2.0 License (found in the LICENSE.Apache file in the root directory). You may select, at your option, one of the above-listed licenses.