The documentation for [sys.dm\_db\_missing\_index\_group\_stats](https://msdn.microsoft.com/en-us/library/ms345421.aspx) uses the terms "user queries" and "system queries" but it doesn't define what those mean. For example:

* user\_seeks: "Number of seeks caused by **user queries** that the recommended index in the group could have been used for."
* system\_seeks: "Number of seeks caused by **system queries**, such as auto stats queries, that the recommended index in the group could have been used for."

Based on the way the term is used at [System query to determine full (including inherited from AD ROLES) view of permissions in a database?](https://stackoverflow.com/questions/11107853/system-query-to-determine-full-including-inherited-from-ad-roles-view-of-permi), I assume that system queries are queries against [system tables](https://msdn.microsoft.com/en-us/library/ms179932.aspx). Then user queries must be queries against [user tables](https://msdn.microsoft.com/en-us/library/ms187406.aspx).

Does anyone have a more authoritative source for the definition of these two terms? I'm asking because I'm using the results from sys.dm\_db\_missing\_index\_group\_stats and considering how to properly weigh avg\_user\_impact vs. avg\_system\_impact in deciding whether to apply an index.