Date and Time Improvements
Applies to: 
SQL Server
Azure SQL Database
Azure SQL Managed Instance
Azure Synapse Analytics
Analytics Platform System (PDW)
This topic describes the OLE DB Driver for SQL Server support for the date and time data types that were added in SQL Server 2008 (10.0.x).
For more information about date/time improvements, see Date and Time Improvements (OLE DB).
Usage
The following sections describe various ways of using the new date and time types.
Use Date as a Distinct Data Type
Beginning with SQL Server 2008 (10.0.x), enhanced support for date/time types makes it more efficient to use the DBTYPE_DBDATE OLE DB type.
Use Time as a Distinct Data Type
OLE DB already has a data type that just contains the time, DBTYPE_DBTIME, which has a precision of 1 second.
The new SQL Server time data type has fractional seconds accurate to 100 nanoseconds. This requires a new type in OLE DB Driver for SQL Server: DBTYPE_DBTIME2. Existing applications written to use times with no fractional seconds can use time(0) columns. The existing OLE DB DBTYPE_TIME type and its corresponding structs should work correctly, unless the applications rely on the type returned in metadata.
Use Time as a Distinct Data Type with Extended Fractional Seconds Precision
Some applications, such as process control and manufacturing applications, require the ability to handle time data with a precision of up to 100 nanoseconds. New type for this purpose in OLE DB is DBTYPE_DBTIME2.
Use Datetime with Extended Fractional Seconds Precision
OLE DB already defines a type with a precision of up to 1 nanosecond. However, this type is already used by existing SQL Server applications and such applications have an expectation of only 1/300 of a second precision. The new datetime2(3) type is not directly compatible with the existing datetime type. If there is a risk that this will affect application behavior, applications must use a new DBCOLUMN flag to determine the actual server type.
Use Datetime with Extended Fractional Seconds Precision and Timezone
Some applications require datetime values with timezone information. This is supported by the new DBTYPE_DBTIMESTAMPOFFSET type.
Use Date/Time/Datetime/Datetimeoffset Data with Client-Side Conversions Consistent with Existing Conversions
The conversions are extended in a consistent manner to include conversions between all date and time types introduced in SQL Server 2008 (10.0.x).