Configuring Microsoft SQL Server/Express Databases

This chapter explains how to create a new server configuration to use Microsoft SQL Server or Microsoft SQL Server Express. Atlas Hub stores everything except for file archives and server startup information in the database of your choice.

You can use the Microsoft Windows version of Atlas Hub with the supported Microsoft databases listed in Supported Databases.

This chapter also provides an overview of the tuning and maintenance SQL scripts that are provided with Atlas Hub and explains how to use them. For detailed information on Microsoft SQL Server performance tuning, consult your Microsoft SQL Server documentation.

Terminology

When this guide uses the terms "instance" and "database", it uses Microsoft terminology. When you install Microsoft SQL Server on a computer, you can install up to 16 instances of it. Each instance can manage a number of different databases. Each Atlas Hub configuration uses its own database. When you perform a typical installation of the Atlas Hub, you install one instance of Microsoft SQL Server Express.

Logging Onto Databases

It is highly recommended that you use a dedicated user account to run or log onto the databases used with Atlas Hub configurations. System administrator accounts usually have unlimited privileges. Any anomalies or errors that occur while you are logged in as the system administrator may result in unrecoverable damage to databases and other databases managed by the same database server.

Understanding the Encoding Differences

Atlas Hub sends data encoded as UTF-8. Microsoft SQL Server and Microsoft SQL Server Express do not support UTF-8 at the database level. They support nchar, nvarchar, and ntext to store fixed format Unicode data (UTF-16).

UTF-8 is a variable length character set in which the characters can expand from one to six bytes depending on the language.
UTF-16 is a fixed length encoding mechanism in which every character expands to two bytes. UTF-16 tends to use up more space than UTF-8 when applied to character sets in which one character always translates to one byte.

Because of how Atlas Hub encodes data, non-English data is human-readable from clients, but not from Microsoft SQL Server and Microsoft SQL Server Express.