What is the best way to check for the existence of a Login in SQL Server 2005.

Question

I am looking for the best way to check that a database login exists in SQL Server 2005. I am currently using

IF suser_sid('loginname') IS NOT NULL

but suser_sid() returns a value in some cases where a login does not exist.

In SQL 2000 we use

SELECT * FROM [Master].[dbo].[sysxlogins] WHERE [name] ='loginname'

but that table does not exist in SQL 2005.

There is a similar question about checking the existence of Users, which is helpful, but I am looking for the existence of Logins.

Answer 1

For sql2005...

select * from master.sys.syslogins WHERE [name] ='loginname'