Open Source C# Database Engines/Servers

Firebird RDBMS offers ANSI SQL features & runs on Linux, Windows & several Unix platforms. Features excellent concurrency & performance & powerful stored procedure & trigger language. More information and downloads at https://firebirdsql.org/, issue tracker is https://github.com/FirebirdSQL/firebird/issues

Duplicati is a free and open source backup client for securely storing your data. Duplicati stores encrypted, incremental, compressed backups on cloud storage services and remote file servers using AES-256 encryption, keeping your data safe and always updated. It works with most storage services, including Google Cloud and Drive, Amazon S3, Microsoft Azure and OneDrive, Dropbox, FTPOpenStack Storage (Swift), SSH (SFTP), WebDAV, Tencent Cloud Object Storage (COS), and more! Duplicati also works on all major platforms (Windows, Linux and OSX). Unlike many other backup solutions, Duplicati ensures that your data is stored securely far away and updated regularly. Incremental updates means it saves on bandwidth and storage space, with a scheduler that automatically keeps your backups up to date.

db4o is the world's leading open source object database for Java and .NET. Leverage fast native object persistence, ACID transactions, query-by-example, S.O.D.A object query API, automatic class schema evolution, small size (http://developer.db4o.com)

SQLite.org took over this project in 2010

Bitwarden Server is an open source project that contains all of the core infrastructure backend of all Bitwarden client applications. This includes APIs, database, Docker and other infrastructure items. Bitwarden is an open source password management solution that stores sensitive information in an encrypted vault. This project is written in C# using .NET Core with ASP.NET Core, while the database is written in T-SQL/SQL Server. Cross-platform, its codebase can be developed, built, run and deployed via Docker containers on Windows, macOS, and Linux distributions.

NeoDatis ODB is a new generation Object Oriented Database. ODB is a real native and transparent persistence layer for Java, .Net, Groovy, Scala and Google Android. ODB is very simple and very fast and comes with a powerful query language.

A free simple ADO.NET compliant MySQL driver. Made in C# but it would be used in all .NET compatible languages.

Object-Relational Main-Memory Embedded Database system tightly integrated with C++ language. Use OS virtual mapping mechanism to access data. Provides subset of SQL language with OO extensions. Support of transactions, fault tolerance, replication.

OpenVista(R) is the open-source version of VistA, an enterprise grade health care information system developed by the U.S. Veterans Affairs and deployed at 1,500 global facilities. OpenVista is a registered trademark of Medsphere Systems Corporation

Provides a .NET 2.0 interface for the Berkeley DB database engine. Written in C#, but accessible to other CLS-compliant languages as well.

A federated search application for discovering interesting files that are being shared online, such as video, music, books, software, games, subtitles and much more. All data is crawled by od-database which collects information about the contents of servers worldwide. We don't search file contents. We host no content, we provide only access to already available files in the same way Google and other search engines do.

A Modern, Portable and Up-To-Date Web Server Package includes Nginx Stable, PHP7 NTS, MariaDB Stable, phpMyAdmin English Stable.

Red/Black Tree implementation. Port of the sourceforge libredblack library to C#. The package also consists of mutlitree (tree with non-unique key) and tree with quick direct access to items by the index.

DBLX 3.3 is available! DBLX is a multi-user, client-server relational database. DBLX uses standard SQL and has many types of clients, and client API's. DBLX has a REST server to allow direct access from web applications. The design goals of DBLX are to produce a very fast database which can be used with standard ANSI sql. DBLX source code is available in C# and Java. DBLX includes the server component, a command-line client, as well as client APIs. DBLX is well-documented so that you can just get the database, drop it on to your favorite system and start using it immediately. Go to the Discussion section to read the latest on DBLX!

flatfiledatabase is a safe and performance flat-file architectural SQL DBMS (Database Management System) .NET Class Library. It is compatible with ufoSQL's file structure.

Extra datalayers for YetAnotherForum >=1.9.x http://yetanotherforum.net created by vzrus.

Simplified ADODB interface library for MySQL on Mono/.NET. The library can be used to port MS ADODB project to an Mono environment.

ADP - Advanced Data Provider - is a transparent factory for ADO.NET which loads providers dynamically. It is written in C# and works on .NET, Portable.NET and Mono on Linux, Windows and MacOSX.

AhMeBa is an XML file-based metabase engine. It targets small data driven applications that don't require a powerfull database engine or need a light, mobile database such as personal websites and small bussiness applications.

The AAL implements specific abstractions built on the .NET that enables teams developing large-scale applications to succeed in an environment of rapid development and customer requirements changes.

Aristotle is an active training simulation that is capable of dynamically and adaptively training any subject in any language using the learners own personality traits and learning modality. This project is currently being developed in PHP/MySQL.

AutoProc (Stored Procedure Generator) is a couple of stored procedures which simplifies generating getter and setter procedures for a given Sql Server 2005/2008 table.

Automated Server Monitor (ASM) has been designed to monitor 1..n servers for service availability. This includes checking any TCP/UDP service, many popular databases including Firebird, MySQL and SQL Server. ASM has been written using Delphi and C#.

Aztec is a command based database application that has similar functionality and uses as SQL. Aztec operates around the "Core-Civilization" enabling interfacing with other applications along with highly customized client and IDE applications.

Encode/Decode library to/from Basic Encoding Rules (BER) of ASN.1 written in Visual Basic .Net. Useful to implement any protocol that uses BER (LDAP, SNMP, etc.).