List of relational database management systems

Open-source software

• CSQL
• Derby aka Java DB
• Firebird
• Gladius DB
• H2
• HSQLDB
• Ingres
• LucidDB [1]
• Mckoi SQL Database
• MonetDB
• MySQL
• Ocelot SQL [2]
• OpenLink Virtuoso (Open Source Edition)
• PostgreSQL
• Quadcap QED
• Rebol sql-protocol
• SmallSQL
• SQLite
• txtSQL

Freeware (proprietary)

• Adabas D
• Advantage Local Server
• IBM DB2 Express-C
• FrontBase
• MaxDB
• Microsoft SQL Server Express
• Oracle Database 10g Express Edition
• Sav Zigzag
• ScimoreDB
• Sybase ASE Express Edition
• tdbengine

Proprietary software not available without cost

• 4th Dimension
• Microsoft Access
• Advantage Database Server
• Alpha_Five
• CA-Datacom
• Dataphor
• Daffodil database
• DB2
• EnterpriseDB
• eXtremeDB
• Faircom c-tree
• FileMaker Pro
• Greenplum
• Helix database
• Informix
• InterBase
• Jbase
• Kognitio, WX2
• Linter
• Matisse
• Microsoft Jet Database Engine (part of Microsoft Access)
• Microsoft SQL Server
• Microsoft Visual FoxPro
• Mimer SQL
• mSQL
• Multivalue
• MySQL
• Netezza
• NonStop SQL
• Oddity Databases
• Openbase
• Oracle
• Oracle Rdb for OpenVMS
• OpenLink Virtuoso Universal Server
• Pervasive
• Pick Post-Relational
• Progress 4GL
• Pyrrho DBMS
• Sand Analytic Server (formerly known as Nucleus)
• SIR (including SIR/XS, SIR2002, SIR2000 ...)
• solidDB
• GUPTA SQLBase
• Sybase SQL Anywhere (formerly known as Sybase Adaptive Server Anywhere and Watcom SQL)
• Sybase Adaptive Server Enterprise
• Sybase Adaptive Server IQ
• Teradata
• ThinkSQL
• TimesTen
• Unify
• Valentina (Database)
• Vertica
• VistaDB
• VMDS
• Whitecross Systems
• WinBase602

Historical

• Britton-Lee IDM
• Micro DBMS
• Oracle Rdb
• Paradox
• PRTV
• QBE
• SQL/DS
• Sybase SQL Server

Truly relational

 Current

• Alphora Dataphor (a proprietary virtual, federated DBMS and RAD MS .Net IDE).
• CsiDB (proprietary C++ library).
• D flat (unreleased MS .Net academic project).
• Duro (free C library).
• Opus (free C libraries).
• Rel (free Java implementation).
• Rosetta (free Perl implementation).
• Aldat (implemented in Relix and JRelix): A pure relational DBMS implemented in McGill University. It features clear syntax and domain algebra operators.

Obsolete

• IBM Business System 12
• IBM IS1
• IBM PRTV (ISBL)
• Multics Relational Data Store
• CDCIM/DM