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Bitwarden primarily stores data in MSSQL (Microsoft SQL Server). The data access layer in the Server is written using Dapper which is a lightweight object mapper for .NET.

Creating the database

See Server Setup Guide.

Updating the database

The dev/migrate.ps1 helper script uses our MsSql Migrator Utility to run migrations. You should run the helper script whenever you sync with the main branch or create a new migration script. Migrations that have already been run are tracked in the Migration table of your database.

Modifying the database

The process for modifying the database is described in Migrations.