Wednesday, October 1, 2008

Renaming SQL Server database objects and changing object owners

What options are available to rename database objects?

SQL Server offers many utilities that you may or may not be aware of and here are specific tools that allow you to rename objects that exist in a SQL Server instance. Each of these commands allows you to make changes to database objects or change ownership of certain objects. The following grid outlines the need, the command and some sample code.

Rename a Database

A database can be renamed in one of several ways. The two commands that SQL Server offers are sp_renamedb and sp_rename. In addition, if you are using SQL Server Management Studio you can also change a database name via the GUI. Another option is to detach and reattach the database and rename the database on the attach. For more information take a look at this previous tip How to rename a database

Example: rename database from Test1 to Test2

sp_renamedb 'Test1' , 'Test2
sp_rename 'Test1', 'Test2', 'DATABASE';

Rename an Object

Another task that you may need to do is to rename an existing table, stored procedure, trigger, etc.. Again this can be done in several ways. You can use the sp_rename stored procedure or use SQL Server Management Studio by right clicking on the object and selecting rename.

Another option is to create a new object and drop the old object.

This could be any object that exists with SQL Server (table, stored procedure, trigger, etc...)

Example: rename object Test1 to Test2.

sp_rename 'dbo.Test1', 'Test2', 'OBJECT';

Rename an Index

Indexes can be renamed using the sp_rename option or again you can create a new index with the new name and drop the old index. Again this can be done using SQL Server Management Studio.

Example: rename an index from Test1 to IX_Test1

sp_rename 'dbo.Test.Test1', 'IX_test1', 'INDEX';

Rename a Column

Renaming a column can be done using the sp_rename stored procedure or you can use ALTER TABLE to add a new column with the new name, move the data to the new column and then drop the old column.

This can also be done using SQL Server Management Studio, by right clicking on the column name and selecting rename.

Example: rename column Product in table Test1 to ProductName

sp_rename 'dbo.Test1.Product', 'ProductName', 'COLUMN';

Change Database Owner

Changing database ownership can be done by using the sp_changedbowner. This can also be done using SQL Server Management Studio under the database properties.

Example: change the current database owner to DBadmin

sp_changedbowner 'DBadmin'

Change Object Owner/Schema

To change the ownership of objects you can use the ALTER SCHEMA command for SQL 2005 or the sp_changeobjectowner for SQL 2000.

Example: change the schema for table Test from the dbo schema to schema TestSchema

--SQL 2005

--SQL 2000
sp_changeobjectowner 'Test', 'TestSchema';

(note: when using SQL Server Management Studio to make these changes, the GUI is just calling the sp_rename stored procedure)

One thing to keep in mind is that when you use these commands or the GUI to rename objects, the change does not get propagated to other objects that are dependent upon the object that you renamed, therefore you will need to make modifications to these other objects in order for them to use the renamed object. As you can see this is a simple way of making these changes, but it could also have negative impact on your application and database. So before you start renaming objects make sure you know the impact of the change first.

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