Summary: The callback loop in InlineSkipList::MultiGet updated finger.prev_[0] as it walked forward through entries (e.g., merge operands). When the MultiGet batch contained duplicate user keys, the next lookup for the same key would find finger.prev_[0] pointing to an entry that sorts AFTER the lookup key in internal key order (because the lookup key has a high sequence number which sorts first), violating the FindSpliceForLevel precondition: before == head_ || KeyIsAfterNode(key, before). Fix: stop updating finger.prev_[0] in the callback loop. Only finger.next_[0] needs advancing to track the walk-forward position. The prev_[0] from FindGreaterOrEqualWithFinger is always a valid lower bound for any subsequent key, whether it uses kMaxSequenceNumber or a snapshot sequence number. Pull Request resolved: https://github.com/facebook/rocksdb/pull/14465 Reviewed By: xingbowang Differential Revision: D96882549 Pulled By: anand1976 fbshipit-source-id: a733fa9d4f23f8b55a027c257a114c4cf35abe2b
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.