I have been told that SQL Native Client is supposed to be faster than the OLEDB drivers. So I put together a utility to do a load-test between the two - and am getting
Also, besides the lack of support for the XML data type, Delphi ADO does not recognize columns defined in SQL Server as TIME (DBTYPE_DBTIME2=145)
or DATETIMEOFFSET (DBTYPE_DBTIMESTAMPOFFSET=146);
trying to use those fields in your application will cause multiple errors like 'Invalid Variant Value' or some controls (like TDBGrid) will simply drop the field entirely.
Seems like the lack of support for DBTYPE_DBTIME2=145
is a bug/QC-issue since there is already ftTime support (it's also not clear to me why SQL Server doesn't return DBTYPE_DBTIME
which Delphi does support), the XML and Offset types have no clear TFieldType mapping.
Data Type Support for OLE DB Date/Time Improvements