Sometimes there is some confusion on the different Command Prompt utilities.

 

I will not go into detail on this, rather providing a collection of the online resources.

 

The short summary is this:

-          ISQL is no longer supported, use SQLCMD

-          ISQL uses DB-LIB (6.5 client level), some SQL 2000 features are not supported, doesn’t support UNICODE input files

-          OSQL uses ODBC, supports UNICODE input files

-          ISQLW is SQL Query Analyzer

-          SQLCMD uses OLE DB

-          SQLNCLI (SNAC / SQL Native Client) combines the OleDb and ODBC provider and has added functionality such as MARS and UDT

 

References for the above:

 

Command Prompt Utilities (SQL Server 2000) -> isql Utility

http://msdn.microsoft.com/en-us/library/aa214007(SQL.80).aspx

Command Prompt Utilities (SQL Server 2000) -> osql Utility

http://msdn.microsoft.com/en-us/library/aa214012.aspx

Command Prompt Utilities (SQL Server 2000) -> isqlw Utility

http://msdn.microsoft.com/en-us/library/aa214005(SQL.80).aspx

 

SQL Server 2005 Books Online (September 2007) -> sqlcmd Utility

http://msdn.microsoft.com/en-us/library/ms162773(SQL.90).aspx

SQL Server 2005 Books Online (September 2007) -> SQL Native Client Programming

http://msdn.microsoft.com/en-us/library/ms130892(SQL.90).aspx

 

SQL Server 2005 Books Online (September 2007) -> Discontinued Database Engine Functionality in SQL Server 2005

http://msdn.microsoft.com/en-us/library/ms144262(SQL.90).aspx          

SQL Server 2008 Books Online (August 2008) -> Discontinued Database Engine Functionality in SQL Server 2008

http://msdn.microsoft.com/en-us/library/ms144262.aspx

 

For protocol specific information, I can recommend the SQL Protocols blog:

http://blogs.msdn.com/sql_protocols/