Those of you that have had the privilege and honor of being in one of my sessions you know I spend a lot to time harping on terminology. I’ve even been known to throw things at people that use the word “site” in a non-ironic fashion. I have been described as “pedantic” a time or two. I wear that badge with pride. 
To that end when I talk about SQL to SharePoint folks some of the terminology gets in the way. I’ve decided to blog a quick and handy “Todd’s guide to SQL Terminology” so that everyone is on the same sheet of music. Here it is:
| Server | Physical box. Something you can kick. Also often used in place of Instance. |
| Instance | SQL process on a server. Has its own settings, databases and security. A server can have many Instances. The default instance is the server’s machine name, the rest are called “named instances” and look like servername\instancename |
| Database | An MDF file and zero or more NDF files. Where the data is actually stored. |
| Transaction Log | An LDF file. Used to store transactions before they’re written to a database |
| File | MDF, NDF or LDF files that store information. |
| Filegroup | A file or group of files that store a partition of a database. |
| Role | SQL security boundary. Roles have permissions, users and logins go into Roles to get permissions. |
I’m sure some SQL folks will have “constructive criticism” about my list. I welcome it. But keep in mind the audience. My audience is SharePoint admins that are afraid of SQL.
tk