readfile_OpenDataSourceXlsx

-- Note: Requires the driver to be installed ahead of time.

-- Enable show advanced options
sp_configure 'show advanced options',1
reconfigure
go

-- Enable ad hoc queries
sp_configure 'ad hoc distributed queries',1
reconfigure
go

-- list available providers
EXEC sp_MSset_oledb_prop

-- Read text file
SELECT * FROM OPENDATASOURCE('Microsoft.ACE.OLEDB.12.0','Data Source=C:\windows\temp\Book1.xlsx;Extended Properties=Excel 8.0')...[Targets$]

-- Note: This also works with unc paths \\ip\file.txt
-- Note: This also works with webdav paths \\ip@80\file.txt However, the target web server needs to support propfind.