How to find the longest string in a varchar column in SQL Server

If you need to find the longest string in a column in a table in SQL Server which has a datatype of varchar(X) or nvarchar(X), where X is a valid integer value for the datatype, then you will need to use the following query:

select MyVarcharColumnName
from MyTableName
where len(MyVarcharColumnName) =
    (select max(len(MyVarcharColumnName))
     from MyTableName)

In the query above you will need to substitute MyVarcharColumnName and MyTableName by your respective column and table names.

Update: [2013-05-18] fixed the code above as suggested by Andy in the comments