The following TechNet Article talks about the SQL Server collation for the SharePoint databases
http://technet.microsoft.com/en-us/library/cc288970.aspx#section1
“The SQL Server collation must be configured for case-insensitive. The SQL Server database collation must be configured for case-insensitive, accent-sensitive, Kana-sensitive, and width-sensitive. This is to ensure file name uniqueness consistent with the Windows operating system.”
However, we do not support changing the default collation (Latin1_General_CI_AS_KS_WS) for SharePoint databases to any other collations (CI, AS, KS, WS).
We support any CI collation for the SQL instance (for master, tempdb databases). However we recommend using Latin1_General_CI_AS_KS_WS as the instance default collation (master, tempdb databases).
Note This is a "FAST PUBLISH" article created directly from within the Microsoft support organization. The information contained herein is provided as-is in response to emerging issues. As a result of the speed in making it available, the materials may include typographical errors and may be revised at any time without notice. See Terms of Use for other considerations.
https://support.microsoft.com/en-in/kb/2008668
https://social.technet.microsoft.com/Forums/en-US/b1e7fcf0-3c20-47b1-af5e-8a6577e5f88e/sharepoint-sql-collation-best-practice?forum=sharepointadmin前のページ