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EElasticsearchElastic N.V. · Vector databasesIn-depth entryDistributed search and analytics engine on Apache Lucene with full-text, aggregations, vector search and ES|QL; triple-licensed AGPL, SSPL and Elastic LicenseAGPL-3.0-only OR SSPL-1.0 OR Elastic-2.0Open sourceFreeSelf-hostedNov 2, 2026
TTimescaleDBTiger Data (formerly Timescale) · Relational databasesPostgreSQL extension for time-series data adding hypertables, compression and continuous aggregates, from the company now named Tiger DataApache-2.0 AND LicenseRef-Timescale-LicenseOpen sourceFreeSelf-hostedNov 2, 2026