Posts Tagged ‘Collation’

SQL DBA – Change a Database Collation in SQL Server

March 25, 2010 3 comments

In previous post I discussed about collation differences b/w different databases/tables and how to query them. The solution was not permanent and every time one has to apply the default collation with the column names while matching them at where clause.

I thought to modify the collation of my database and tables on my new database and make it compatible to my old database. However this is not advisable for existing DBs, because collation setting within databases is done intentionally and for some purpose.

I issued the following sql statement to alter the database collation level:

alter database someDatabase collate SQL_Latin1_General_CP437_BIN

But it ended up on the following error:

Msg 5030, Level 16, State 2, Line 1
The database could not be exclusively locked to perform the operation.
Msg 5072, Level 16, State 1, Line 1
ALTER DATABASE failed. The default collation of database 'someDatabase' 
cannot be set to SQL_Latin1_General_CP437_BIN.

Then I came to know that the database has to be in single user mode, so that I can apply the changes. So I issued the following sql statements:

ALTER DATABASE someDatabase COLLATE SQL_Latin1_General_CP437_BIN

… and yes they get successfully executed. I checked the collation and it got changed to the new one.
But for the existing tables I had to manually change the collation of each & every tables by applying following sql statements:

alter table someTable alter column [someColumnX] varchar(9) COLLATE SQL_Latin1_General_CP437_BIN

SQL DBA – Collation Conflict in SQL Server

February 23, 2010 6 comments

Cannot resolve the collation conflict between “SQL_Latin1_General_CP437_BIN” and “SQL_Latin1_General_CP1_CI_AS” in the equal to operation.

Just few days back I came across this error when I tried to join two tables from 2 different databases. Didn’t get any clue for a few minutes so I googled up this error (Thanks google baba).

Collation is MS SQL Server is used for specifying the ordering of characters when you create or alter a table or create a domain. Collation settings, which include character set, sort order, and other locale-specific settings, are fundamental to the structure and function of Microsoft SQL Server databases. SQL Server uses them implicitly in SQL statements. To use them explicitly you need to override the default collation or the collation you specified when creating or altering the table or creating the domain. Collation can be applied for char, varchar, text, nchar, nvarchar, and ntext data types.

For example:

SELECT T1.EmployeeName, T2.DeptName
FROM ServerA.dbo.EmpTab T1
JOIN ServerB.dbo.DeptTab T2
ON T1.DeptCode = T2.DeptCode

There could be a possibility that both the servers use different Collations. If yes then you would get an error similar to then one I mentioned at the top of this topic. What you should do in this case?
1. You can alter the default Collation of either of the table columns/fields, but this could have a ripple effect for other tables currently in use with the altered table.
2. Use COLLATE DATABASE_DEFAULT keyword while matching the columns/fields, like:

SELECT T1.EmployeeName, T2.DeptName
FROM ServerA.dbo.EmpTab T1
JOIN ServerB.dbo.DeptTab T2

More Info:
Collation Types:
Alter Table:
Alter Database: