MDAC 2.5 SDK - ODBC Programmer's Reference
Chapter 18: Installing ODBC Components

ODBC Header Files

Note   Redistribution of ODBC header files is not required. None are considered "Core".

Header Files

Odbcinst.h
Sql.h
Sqlext.h
Sqltypes.h
Sqlucode.h
Msdasql.h
Msdadc.h