06ab0a8b40
Summary: The patch extends the iterator API with a new `columns` method which can be used to retrieve all wide columns for the current key. Similarly to the `Get` and `GetEntity` APIs, the classic `value` API returns the value of the default (anonymous) column for wide-column entities, and `columns` returns an entity with a single default column for plain old key-values. (The goal here is to maintain the invariant that `value()` is the same as the value of the default column in `columns()`.) The patch also involves a smaller refactoring: historically, `value()` was implemented using a bunch of conditions, that is, the `Slice` to be returned was decided based on the direction of the iteration, whether a merge had been done etc. when the method was called; with the patch, the value to be exposed is stored in a member `Slice value_` when the iterator lands on a new key, and `value()` simply returns this `Slice`. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10670 Test Plan: Ran `make check` and a simple blackbox crash test. Reviewed By: riversand963 Differential Revision: D39475551 Pulled By: ltamasi fbshipit-source-id: 29e7a6ed9ef340841aab36803b832b7c8f668b0b |
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| LANGUAGE-BINDINGS.md | ||
| LICENSE.Apache | ||
| LICENSE.leveldb | ||
| Makefile | ||
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README.md
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.