SQL Server – How to Remove a Period If It Is the First Character in a Varchar Column

"The first shall be last, and the last shall be first"

REVERSE(STUFF ( REVERSE(lastname), 1, 1, ''))

It seems that this behavior / ability is both known and deprecated. I was looking through the sys.dm_os_performance_counters DMV the other day and noticed the following two entries:

object_name                      counter_name    instance_name
-----------------------------    ------------    -------------------------------
SQLServer:Deprecated Features    Usage           '@' and names that start with '@@' as
                                                 Transact-SQL identifiers

SQLServer:Deprecated Features    Usage           '#' and '##' as the name of temporary
                                                 tables and stored procedures

I then checked the MSDN documentation and found both of these noted on the Deprecated Database Engine Features in SQL Server 2016 page, in the Features Not Supported in a Future Version of SQL Server section, under the Category of "Transact-SQL":

Deprecated feature                     Replacement                               Feature ID
-----------------------------------    --------------------------------------    ----------
Use of #, ## as temporary table and    Use at least one additional character.    185
temporary stored procedure names.

Use of @, @@, or @@ as                 Do not use @ or @@ or names that begin    186
Transact-SQL identifiers.              with @@ as identifiers.

The earliest reference I could find for this deprecation notice was in the SQL Server 2008 documentation. And while the version drop-down on that "Deprecated Database Engine Features" page does not have an entry for SQL Server 2005, you can still get to that documentation via, https://msdn.microsoft.com/en-us/library/ms143729(v=sql.90).aspx, and see that neither of these items are listed.

That information leads me to the following conclusions:

• Question Part 1 (is this a bug or intended behavior):

  It is intended, albeit undesirable, behavior.

• Question Part 2 (is there a benefit to this behavior):

  Not only does there not seem to be any beneficial use-case here, even if there was, it wouldn't matter too much due to this behavior / ability being deprecated and hence not something that should be used going forward, especially in new code / projects.