1. Now open command prompt as Administrator user and navigate to the Setup.exe on installation media or local copy of setup.exe. In default installation setting; you’ll find this file here: (ตำแหน่งของไฟล์ Setup โปรแกรม SQL Server)
2. Next the command you want to run has following syntax:
Setup /QUIET /ACTION=REBUILDDATABASE /INSTANCENAME=<Your Instance Name> /SQLSYSADMINACCOUNTS=<Your SQL SYS Admin account> [ /SAPWD=<Password> ] /SQLCOLLATION=<Your New SQL Collation name>
Ex. setup /QUIET /ACTION=RebuildDatabase /INSTANCENAME=”SQLEXPRESS” /SAPWD=”password user sa” /SQLCOLLATION=”SQL_Latin1_General_CP1_CI_AS” /SQLSYSADMINACCOUNTS=”user admin on PC”
3. Hit enter and you are done.
URL : http://www.carryoverbit.com/changing-default-collation-of-microsoft-sql-server-2012/