When working with SQL Server, it’s important to understand the various registry keys that are associated with the installation and configuration of the server. These registry keys hold important information about the server instance, such as the installation directory, version number, and various settings.

In SQL Server 2005, working with registry keys became more challenging due to two major reasons. First, each instance of a SQL Server product is given a unique directory name at installation, making it harder to locate the corresponding registry keys. Second, Microsoft tightened the security of its undocumented extended procedures for reading and writing registry keys, making it more difficult to access this information.

While there are sanctioned front ends and function calls to access some of this information, it can be useful to have a comprehensive view of all the registry keys at once, especially when comparing server instances on the same hardware. To address this need, a Perl utility called SqlRegKeys.pl was developed.

The SqlRegKeys.pl utility allows you to examine one or all registry keys for a specific SQL instance on a local or remote server. It also provides the ability to set the value of a registry key for a single server instance. The utility is easy to use and can be run from the command line.

For example, to retrieve the SQLDataRoot value for a specific instance, you can run the following command:

Perl SqlRegKeys.pl \\ServerName\InstanceName SQLDataRoot

This will display the SQLDataRoot value for the specified instance. Similarly, you can set the value of a registry key by providing an additional parameter:

Perl SqlRegKeys.pl \\ServerName\InstanceName SQLDataRoot "C:\MSSQL\Data"

This will set the SQLDataRoot value to “C:\MSSQL\Data” for the specified instance.

The utility also allows you to compare registry keys across multiple server instances. This can be useful for ensuring consistency in settings or identifying differences between instances. For example, you can compare the Version value across all instances by running:

Perl SqlRegKeys.pl \\ServerName\ALL Version

This will display the Version value for all instances on the specified server.

It’s important to note that modifying registry keys should be done with caution and only by knowledgeable professionals. Microsoft does not provide official documentation on the purpose and safety of each registry key, and modifying them incorrectly can cause serious issues with the SQL Server installation.

While the SqlRegKeys.pl utility provides a convenient way to explore and modify SQL Server registry keys, it’s important to exercise caution and backup the registry before making any changes. It’s also recommended to test any modifications on development servers before applying them to production environments.

In conclusion, understanding and working with SQL Server registry keys can provide valuable insights into the configuration and behavior of the server. The SqlRegKeys.pl utility offers a convenient way to explore and modify these keys, but it’s important to approach registry modifications with caution and follow best practices to avoid any potential issues.