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HyPer: A hybrid OLTP&OLAP main memory database system based on virtual memory snapshots
TLDR
This work presents an efficient hybrid system, called HyPer, that can handle both OLTP and OLAP simultaneously by using hardware-assisted replication mechanisms to maintain consistent snapshots of the transactional data.
How Good Are Query Optimizers, Really?
TLDR
This paper introduces the Join Order Benchmark (JOB) and experimentally revisit the main components in the classic query optimizer architecture using a complex, real-world data set and realistic multi-join queries.
The adaptive radix tree: ARTful indexing for main-memory databases
Main memory capacities have grown up to a point where most databases fit into RAM. For main-memory database systems, index structure performance is a critical bottleneck. Traditional in-memory data
Learned Cardinalities: Estimating Correlated Joins with Deep Learning
TLDR
This work describes a new deep learning approach to cardinality estimation that builds on sampling-based estimation, addressing its weaknesses when no sampled tuples qualify a predicate, and in capturing join-crossing correlations.
Heuristic and randomized optimization for the join ordering problem
TLDR
It turns out that randomized and genetic algorithms are well suited for optimizing join expressions and generate solutions of high quality within a reasonable running time.
Fast Serializable Multi-Version Concurrency Control for Main-Memory Database Systems
TLDR
This work presents a novel MVCC implementation for main-memory database systems that has very little overhead compared to serial execution with single-version concurrency control and verifies that the (extensional) writes of recently committed transactions do not intersect with the (intensional) read predicate space of a committing transaction.
Multi-tenant databases for software as a service: schema-mapping techniques
TLDR
A new schema-mapping technique for multi-tenancy called Chunk Folding is described, where the logical tables are vertically partitioned into chunks that are folded together into different physical multi-Tenant tables and joined as needed.
Morsel-driven parallelism: a NUMA-aware query evaluation framework for the many-core age
TLDR
The morsel-driven query execution framework is presented, where scheduling becomes a fine-grained run-time task that is NUMA-aware and the degree of parallelism is not baked into the plan but can elastically change during query execution, so the dispatcher can react to execution speed of different morsels but also adjust resources dynamically in response to newly arriving queries in the workload.
The mixed workload CH-benCHmark
TLDR
The definition of a new, complex, mixed workload benchmark, called mixed workload CH-benCHmark, which bridges the gap between the established single-workload suites of TPC-C for OLTP and T PC-H for OLAP, and executes a complex mixed workload.
Workload Analysis and Demand Prediction of Enterprise Data Center Applications
TLDR
A trace based approach for capacity management that relies on the characterization of workload demand patterns, the generation of synthetic workloads that predict future demands based on the patterns, and a workload placement recommendation service to automate the efficient use of resource pools when hosting large numbers of enterprise services.
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