Databases with Intra-Operator (Horizontal) Parallel Execut...


	1010data OLAP	2000	Relational	Inter-Operator (Vertical), Intra-Operator (Horizontal)	OLAP
	Adaptive Server Enterprise Acquired Company	1987	Relational	Inter-Operator (Vertical), Intra-Operator (Horizontal)	Acquired Company
	AlloyDB OLAP Forked Code OLTP	2022	Relational	Inter-Operator (Vertical), Intra-Operator (Horizontal)	OLAP Forked Code OLTP
	Altibase OLTP	1999	Relational	Inter-Operator (Vertical), Intra-Operator (Horizontal)	OLTP
	AresDB OLAP Abandoned	2018	Relational	Intra-Operator (Horizontal)	OLAP Abandoned
	Atoti OLAP	2005	Relational	Intra-Operator (Horizontal)	OLAP
	Azure HorizonDB	2026	Relational	Intra-Operator (Horizontal)
	CedarDB OLAP Forked Code OLTP	2023	Relational, Array / Matrix	Intra-Operator (Horizontal)	OLAP Forked Code OLTP
	chDB OLAP Acquired Company AI-Assisted	2023	Relational	Intra-Operator (Horizontal), Inter-Operator (Vertical)	OLAP Acquired Company AI-Assisted
	ClickHouse OLAP AI-Assisted	2016	Relational	Intra-Operator (Horizontal), Inter-Operator (Vertical)	OLAP AI-Assisted
	Cubrick	2016	Column Family / Wide-Column	Intra-Operator (Horizontal)
	DataFusion Query Engine AI-Assisted	2016	Relational	Intra-Operator (Horizontal)	Query Engine AI-Assisted
	Drill OLAP AI-Assisted	2012	Column Family / Wide-Column	Intra-Operator (Horizontal)	OLAP AI-Assisted
	DuckDB OLAP AI-Assisted	2018	Relational	Intra-Operator (Horizontal), Inter-Operator (Vertical)	OLAP AI-Assisted
GA	Gamma OLAP Abandoned OLTP	1986	Relational	Bushy, Inter-Operator (Vertical), Intra-Operator (Horizontal)	OLAP Abandoned OLTP
	Gel OLAP AI-Assisted	2018	Relational	Intra-Operator (Horizontal)	OLAP AI-Assisted
	GridGain	2007	Key/Value	Intra-Operator (Horizontal)
	Hadapt OLAP Acquired Company Middleware	2009	Relational	Inter-Operator (Vertical), Intra-Operator (Horizontal)	OLAP Acquired Company Middleware
	HexaDB	2023	Relational	Intra-Operator (Horizontal)
	HoraeDB Time-Series Abandoned	2021	Relational	Intra-Operator (Horizontal)	Time-Series Abandoned
	HyperGraphDB	2007	Graph	Intra-Operator (Horizontal)
	Ignite	2014	Key/Value	Intra-Operator (Horizontal)
	JuliaDB Abandoned	2017	Relational	Intra-Operator (Horizontal)	Abandoned
	Kappa Abandoned	1989	Relational	Intra-Operator (Horizontal)	Abandoned
LI	libmdbx Forked Code MMAP	2015	Key/Value	Intra-Operator (Horizontal), Inter-Operator (Vertical)	Forked Code MMAP
	LMDB MMAP DBM AI-Assisted	2011	Key/Value	Intra-Operator (Horizontal), Inter-Operator (Vertical)	MMAP DBM AI-Assisted
	Materialize Streaming AI-Assisted	2019	Relational	Intra-Operator (Horizontal), Inter-Operator (Vertical)	Streaming AI-Assisted
	Memgraph AI-Assisted	2016	Graph	Intra-Operator (Horizontal)	AI-Assisted
	Mimir Time-Series AI-Assisted	2016	Relational	Intra-Operator (Horizontal)	Time-Series AI-Assisted
	MonetDB OLAP MMAP	2002	Column Family / Wide-Column	Intra-Operator (Horizontal)	OLAP MMAP
	MotherDuck Hosting Service	2022	Relational	Intra-Operator (Horizontal), Inter-Operator (Vertical)	Hosting Service
	Multigres Middleware AI-Assisted	2025	Relational	Intra-Operator (Horizontal)	Middleware AI-Assisted
	Netezza OLAP Acquired Company	1999	Relational	Inter-Operator (Vertical), Intra-Operator (Horizontal)	OLAP Acquired Company
	NoisePage	2018	Relational	Intra-Operator (Horizontal)
	ObsessionDB OLAP Hosting Service	2024	Relational	Intra-Operator (Horizontal), Inter-Operator (Vertical)	OLAP Hosting Service
	OceanBase	2010	Relational	Inter-Operator (Vertical), Intra-Operator (Horizontal)
OP	open-gpdb OLAP Forked Code	2024	Relational	Inter-Operator (Vertical), Intra-Operator (Horizontal)	OLAP Forked Code
	OpenTSDB Time-Series	2010	Key/Value	Intra-Operator (Horizontal)	Time-Series
	ParStream OLAP Acquired Company Abandoned	2010	Relational	Intra-Operator (Horizontal)	OLAP Acquired Company Abandoned
	Polars Query Engine AI-Assisted	2020	—	Intra-Operator (Horizontal)	Query Engine AI-Assisted
	PosDB OLAP	2017	Relational	Inter-Operator (Vertical), Intra-Operator (Horizontal)	OLAP
	PostgreSQL OLTP	1986	Relational	Intra-Operator (Horizontal)	OLTP
	Proton Streaming AI-Assisted	2021	Relational	Intra-Operator (Horizontal)	Streaming AI-Assisted
	QuestDB Time-Series AI-Assisted	2014	Relational	Intra-Operator (Horizontal)	Time-Series AI-Assisted
	Quickstep OLAP Abandoned	2013	Relational	Intra-Operator (Horizontal)	OLAP Abandoned
	RaptorDB Forked Code	2024	Relational	Intra-Operator (Horizontal)	Forked Code
	RexDB Acquired Company	2006	Relational	Intra-Operator (Horizontal)	Acquired Company
	Rockset OLAP Acquired Company	2016	Relational	Intra-Operator (Horizontal)	OLAP Acquired Company
	SequoiaDB	2011	Document / XML	Intra-Operator (Horizontal)
	Sirius OLAP Query Engine AI-Assisted	2024	Relational	Intra-Operator (Horizontal)	OLAP Query Engine AI-Assisted
	Skyrise OLAP Serverless Query Engine	2019	Relational	Inter-Operator (Vertical), Intra-Operator (Horizontal)	OLAP Serverless Query Engine
	Splunk Acquired Company Search Engine	2002	Key/Value	Inter-Operator (Vertical), Intra-Operator (Horizontal)	Acquired Company Search Engine
	StarRocks OLAP AI-Assisted	2021	Relational, Column Family / Wide-Column	Intra-Operator (Horizontal)	OLAP AI-Assisted
	SurrealDB Serverless Multi-Model AI-Assisted	2016	Document / XML, Graph, Relational	Intra-Operator (Horizontal), Inter-Operator (Vertical)	Serverless Multi-Model AI-Assisted
	Swarm64 OLAP Acquired Company	2013	Relational	Intra-Operator (Horizontal)	OLAP Acquired Company
	SWC-DB Abandoned	2019	Column Family / Wide-Column, Key/Value	Inter-Operator (Vertical), Intra-Operator (Horizontal)	Abandoned
	Tajo OLAP Abandoned	2012	Relational	Intra-Operator (Horizontal)	OLAP Abandoned
	Tibero OLTP	2003	Relational	Inter-Operator (Vertical), Intra-Operator (Horizontal)	OLTP
	TileDB NoSQL	2014	Array / Matrix	Intra-Operator (Horizontal)	NoSQL
	TransLattice NewSQL Failed Company	2007	Relational	Intra-Operator (Horizontal)	NewSQL Failed Company
	Umbra OLAP OLTP	2018	Array / Matrix, Relational	Intra-Operator (Horizontal), Inter-Operator (Vertical), Bushy	OLAP OLTP
	Valkey Cache Forked Code NoSQL AI-Assisted	2024	Key/Value	Intra-Operator (Horizontal), Inter-Operator (Vertical)	Cache Forked Code NoSQL AI-Assisted
	Xata Forked Code AI-Assisted	2020	Relational	Intra-Operator (Horizontal)	Forked Code AI-Assisted
	Yellowbrick OLAP	2014	Relational	Intra-Operator (Horizontal)	OLAP