MS SQL

Microsoft SQL Server is supported by the core better_auth gem through the direct MSSQL adapter for Rack applications.

Install Dependencies

gem "better_auth"
gem "sequel"
gem "tiny_tds"

bundle install

Example Usage

require "better_auth"

auth = BetterAuth.auth(
  secret: ENV.fetch("BETTER_AUTH_SECRET"),
  base_url: ENV.fetch("BETTER_AUTH_URL"),
  database: ->(options) {
    BetterAuth::Adapters::MSSQL.new(
      options,
      url: ENV.fetch("DATABASE_URL")
    )
  }
)

You may also pass an existing Sequel database object when your app owns connection management.

require "sequel"
require "tiny_tds"

database = Sequel.connect(ENV.fetch("DATABASE_URL"))

auth = BetterAuth.auth(
  secret: ENV.fetch("BETTER_AUTH_SECRET"),
  database: ->(options) {
    BetterAuth::Adapters::MSSQL.new(
      options,
      connection: database
    )
  }
)

Schema generation & migration

The Ruby schema helpers generate MSSQL DDL from the same Better Auth configuration used at runtime, including plugins, custom model names, custom field names, and additional_fields.

config = BetterAuth::Configuration.new(
  secret: ENV.fetch("BETTER_AUTH_SECRET"),
  database: :memory,
  plugins: []
)

statements = BetterAuth::Schema::SQL.create_statements(
  config,
  dialect: :mssql
)

puts statements.join("\n\n")

require "better_auth"
require "sequel"
require "tiny_tds"

config = BetterAuth::Configuration.new(
  secret: ENV.fetch("BETTER_AUTH_SECRET"),
  database: :memory,
  plugins: []
)

statements = BetterAuth::Schema::SQL.create_statements(
  config,
  dialect: :mssql
)

database = Sequel.connect(ENV.fetch("DATABASE_URL"))
statements.each { |sql| database.run(sql) }

Joins (Experimental)

Enable experimental joins when you want Better Auth to ask the database adapter to fetch related records in one adapter call.

auth = BetterAuth.auth(
  secret: ENV.fetch("BETTER_AUTH_SECRET"),
  experimental: { joins: true },
  database: ->(options) {
    BetterAuth::Adapters::MSSQL.new(
      options,
      url: ENV.fetch("DATABASE_URL")
    )
  }
)

The MSSQL adapter supports native joins for core relationships and for plugin schema relationships declared with references.

Schema

The Ruby schema maps Better Auth logical fields to MSSQL physical columns.

JSON-like fields are stored as varchar(8000) JSON strings and parsed on output, date fields use datetime2(3), indexed strings use varchar(255), and ids are generated as hex strings by default. Set advanced: { database: { generate_id: "uuid" } } to generate UUID strings instead.

Additional Information

• The direct adapter supports the shared Better Auth CRUD contract, where operators, sorting, pagination, counts, Sequel-backed transactions, and native joins.
• The DATABASE_URL should use a Sequel/TinyTDS-compatible connection URL.
• Direct SQL generation is intended for non-Rails apps or custom migration workflows.