Set or change the server collation
The server collation acts as the default collation for all system databases that are installed with the instance of SQL Server, and also any newly created user databases.
You should carefully consider the server-level collation, because it may affect:
- Sorting and comparison rules in
ORDER BYand other operators that compare textual data.
- Collation of the
NVARCHARcolumns in system views, system functions, and the objects in
tempdb(for example, temporary tables).
- Names of the variables, cursors, and
GOTOlabels. For example, the variables
@PIare considered as different variables if the server-level collation is case-sensitive, and the same variables if the server-level collation is case-insensitive.
Server collation in SQL Server
The server collation is specified during SQL Server installation. The default server-level collation is based upon the locale of the operating system.
For example, the default collation for systems using US English (en-US) is SQL_Latin1_General_CP1_CI_AS. For more information, including the list of OS locale to default collation mappings, see the "Server-level collations" section of Collation and Unicode Support.
The server-level collation for SQL Server Express LocalDB is SQL_Latin1_General_CP1_CI_AS and cannot be changed, either during or after installation.
Change the server collation in SQL Server
Changing the default collation for an instance of SQL Server can be a complex operation.
Instead of changing the default collation of an instance of SQL Server, you can specify a default collation for each new database you create via the
COLLATE clause of the
CREATE DATABASE and
ALTER DATABASE statements. For more information, see Set or Change the Database Collation.
Changing the instance collation involves the following steps:
Make sure you have all the information or scripts needed to re-create your user databases and all the objects in them.
Drop all the user databases.
masterdatabase specifying the new collation in the
SQLCOLLATIONproperty of the
setupcommand. For example:
Setup /QUIET /ACTION=REBUILDDATABASE /INSTANCENAME=InstanceName /SQLSYSADMINACCOUNTS=accounts /[ SAPWD= StrongPassword ] /SQLCOLLATION=CollationName
For more information, see Rebuild System Databases.
Create all the databases and all the objects in them.
Import all your data.
Set the server collation in Azure SQL Managed Instance
Server-level collation in Azure SQL Managed Instance can be specified when the instance is created and cannot be changed later. You can set server-level collation via Azure portal or PowerShell and Resource Manager template while you are creating the instance. Default server-level collation is SQL_Latin1_General_CP1_CI_AS.
If you are migrating databases from SQL Server to Azure SQL Managed Instance, check the server collation in the source SQL Server using
SERVERPROPERTY(N'Collation') function and create a managed instance that matches the collation of your SQL Server. Migrating a database from SQL Server to SQL Managed Instance with the server-level collations that are not matched might cause several unexpected errors in the queries. You cannot change the server-level collation on the existing managed instance.
Collations in Azure SQL Database
You cannot change or set the logical server collation on Azure SQL Database, but can configure each database's collations both for data and for the catalog. The catalog collation determines the collation for system metadata, such as object identifiers. Both collations can be specified independently when you create the database in the Azure portal, in T-SQL with CREATE DATABASE, in PowerShell with New-AzSqlDatabase.