Open-source DB that can work with applications written for Microsoft SQL Server

WiltonDB consists of a modified PostgreSQL with a set of Babelfish extensions packaged for Windows. It strives to be useable as a drop-in replacement to Microsoft SQL Server. It understands MSSQL dialect (T-SQL) and can run existing queries and stored procedures for your application. It also understands MSSQL wire protocol (TDS) so applications can use the same DB drivers (ADO.NET, ODBC, JDBC) to connect to WiltonDB.

FAQ

Question 1: If this is Babelfish built for Windows, why is it called "WiltonDB" not "Babelfish for Windows"?

Babelfish open-source project officially does not support Windows. Babelfish codebase relies on a number of assumptions about the toolchain (for example: 128-bit integer support, variable-length struct fields, extern variables visibility) that are incompatible with MSVC compiler. Windows porting patches applied to Babelfish are numerous and not trivial, if WiltonDB misbehaves or crashes when running with your application on Windows, it does not necessary mean that Babelfish running on Linux will have the same problem (please report such problems/discrepancies to us, we will try to fix them).

Question 2: Is Babelfish/WiltonDB 100% compatible with MSSQL?

No, it is not, though in recent versions compatibility is quite high, see details in Babelfish documentation. Please also note, that in many cases Babelfish relies on native PostgreSQL implementation, and behaviour of the same standard SQL functionality may be slightly different (for example, datetime string parsing is more lenient than in MSSQL).

Question 3: Can I run WiltonDB on Linux?

Yes, we maintain WiltonDB packages for Ubuntu and RHEL built from exactly the same sources that are used for Windows MSI. While compiling vanilla Babelfish from source is relatively straightforward, WiltonDB DEB and RPM packages follow distro conventions for DB cluster/config placement and provide integration with systemd.

Question 4: Do you provide managed instances of WiltonDB to be used with applications deployed in a cloud?

No, WiltonDB is distributed and supported only as a standalone Windows installer MSI package and as Linux DEB and RPM packages. For cloud deployments please consider using Babelfish for Amazon Aurora. WiltonDB Software is not affiliated with AWS (beyond being a minor contributor to open-source Babelfish). Though WiltonDB project would not be possible without the work and dedication of the dozens of people who have contributed to creation of Babelfish at AWS and then have graciously made it open-source. Everyone involved in the development of Babelfish has our gratitude.

License

WiltonDB is released under the Apache-2.0 or PostgreSQL license at your choice. Use is permitted under either license.