cockroachdb/cockroach
Papers Referenced in This Repository
Algorithms for geodesics
Algorithms for the computation of geodesics on an ellipsoid of revolution are given. These provide accurate, robust, and fast solutions to the direct and inverse geodesic problems and they allow differential and integral properties of geodesics to be computed.
Elle: Inferring Isolation Anomalies from Experimental Observations
Users who care about their data store it in databases, which (at least in principle) guarantee some form of transactional isolation. However, experience shows [Kleppmann 2019, Kingsbury and Patella 2019a] that many databases do not provide the isolation guarantees they claim. With the recent prolife...
The serializability of concurrent database updates
ABSTRACT A sequence of interleaved user transactions in a database system may not be ser:ahzable, t e, equivalent to some sequential execution of the individual transactions Using a simple transaction model, it ~s shown that recognizing the transaction histories that are serlahzable is an NP-complet...
Weighted Random Sampling over Data Streams
In this work, we present a comprehensive treatment of weighted random sampling (WRS) over data streams. More precisely, we examine two natural interpretations of the item weights, describe an existing algorithm for each case ([2, 4]), discuss sampling with and without replacement and show adaptation...
One WITH RECURSIVE is Worth Many GOTOs
PL/SQL integrates an imperative statement-by-statement style of programming with the plan-based evaluation of SQL queries. The disparity of both leads to friction at runtime, slowing PL/SQL execution down significantly. This work describes a compiler from PL/SQL UDFs to plain SQL queries. Post-compi...
On the correct and complete enumeration of the core search space
Reordering more than traditional joins (e.g. outerjoins, antijoins) requires some care, since not all reorderings are valid. To prevent invalid plans, two approaches have been described in the literature. We show that both approaches still produce invalid plans.
RaBitQ: Quantizing High-Dimensional Vectors with a Theoretical Error Bound for Approximate Nearest Neighbor Search
Searching for approximate nearest neighbors (ANN) in the high-dimensional Euclidean space is a pivotal problem. Recently, with the help of fast SIMD-based implementations, Product Quantization (PQ) and its variants can often efficiently and accurately estimate the distances between the vectors and h...
Low-Latency Sliding-Window Aggregation in Worst-Case Constant Time
Sliding-window aggregation is a widely-used approach for extracting insights from the most recent portion of a data stream. The aggregations of interest can usually be cast as binary operators that are associative, but they are not necessarily commutative nor invertible. Non-invertible operators, ho...