MSSQL Connectivity

Hello Can I connect to MS SQL Server using Libre Office Calc & execute queries.? If yes please let me know the steps.

Yes. If you have registered your MSSQL database as an ODBC datasource, you will be able to connect to it through Calc and Base.

View your Calc Data Sources through View > Data Sources, or press F4 in Calc.

A more comprehensive guide can be found here:
http://www.easysoft.com/applications/openoffice_org/odbc.html