> For the complete documentation index, see [llms.txt](https://docs.ngsurvey.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ngsurvey.com/installation-setup/installation/database-backend.md).

# Database Backend

ngSurvey can be run using any of the following databases as its backend. 

* [Microsoft SQL Server](/installation-setup/installation/database-backend/microsoft-sql-server.md)
* [MySQL](/installation-setup/installation/database-backend/oracle-mysql.md)
* [MariaDB](/installation-setup/installation/database-backend/mariadb.md)
* [PostgreSQL](/installation-setup/installation/database-backend/postgresql.md)

{% hint style="danger" %}
Once setup its  currently not possible to migrate an existing ngSurvey database from one database vendor to another database vendor.
{% endhint %}


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