| Member name | Description |
|---|
| DT_BOOL | A Boolean value. |
| DT_BYREF_BOOL | A pointer to a Boolean value. |
| DT_BYREF_CY | A pointer to a currency value. This data type is an 8-byte value with a scale of 4 and a maximum precision of 19. |
| DT_BYREF_DATE | A pointer to a date structure that consists of year, month, date, and hour. |
| DT_BYREF_DBDATE | A pointer to a date structure that consists of year, month, and date. |
| DT_BYREF_DBTIME | A pointer to a time structure that consists of hour, minute, and second. |
| DT_BYREF_DBTIME2 | A pointer to a time structure that consists of hour, minute, second, and fractional seconds. The fractional seconds have a maximum scale of 7 digits. |
| DT_BYREF_DBTIMESTAMP | A pointer to a timestamp structure that consists of year, month, day, hour, minute, second, and fractional seconds. The fractional seconds have a maximum scale of 3 digits. |
| DT_BYREF_DBTIMESTAMP2 | A pointer to a timestamp structure that consists of year, month, day, hour, minute, second, and fractional seconds. The fractional seconds have a maximum scale of 7 digits. |
| DT_BYREF_DBTIMESTAMPOFFSET | A pointer to a timestamp structure that consists of year, month, day, hour, minute, second, and fractional seconds. The fractional seconds have a maximum scale of 7 digits. |
| DT_BYREF_DECIMAL | A pointer to an exact numeric value with a fixed precision and a fixed scale. This data type is a 12-byte value with a separate sign, a scale of 0 to 28, and a maximum precision of 29. |
| DT_BYREF_FILETIME | A pointer to a 64-bit value that represents the number of 100-nanosecond intervals since January 1, 1601. |
| DT_BYREF_GUID | A pointer to a GUID. |
| DT_BYREF_I1 | A pointer to a 1-byte, signed integer. |
| DT_BYREF_I2 | A pointer to a 2-byte, signed integer. |
| DT_BYREF_I4 | A pointer to a 4-byte, signed integer. |
| DT_BYREF_I8 | A pointer to an 8-byte, signed integer. |
| DT_BYREF_NUMERIC | A pointer to an exact numeric value with a fixed precision and scale. This data type is a 16-byte value with a separate sign, a scale of 0 to 38, and a maximum precision of 38. |
| DT_BYREF_R4 | A pointer to a single-precision floating-point value. |
| DT_BYREF_R8 | A pointer to a double-precision floating-point value. |
| DT_BYREF_UI1 | A pointer to a 1-byte, unsigned integer. |
| DT_BYREF_UI2 | A pointer to a 2-byte, unsigned integer. |
| DT_BYREF_UI4 | A pointer to a 4-byte, unsigned integer. |
| DT_BYREF_UI8 | A pointer to an 8-byte, unsigned integer. |
| DT_BYTES | A binary data value. The length is variable and the maximum length is 8,000 bytes. |
| DT_CY | A currency value. This data type is an 8-byte value with a scale of 4 and a maximum precision of 19. |
| DT_DATE | A date structure that consists of year, month, day, and hour. |
| DT_DBDATE | A date structure that consists of year, month, and date. |
| DT_DBTIME | A time structure that consists of hour, minute, and second. |
| DT_DBTIME2 | A time structure that consists of hour, minute, second, and fractional seconds. The fractional seconds have a maximum scale of 7 digits. |
| DT_DBTIMESTAMP | A timestamp structure that consists of year, month, day, hour, minute, second, and fractional seconds. The fractional seconds have a maximum scale of 3 digits. |
| DT_DBTIMESTAMP2 | A timestamp structure that consists of year, month, day, hour, minute, second, and fractional seconds. The fractional seconds have a maximum scale of 7 digits. |
| DT_DBTIMESTAMPOFFSET | A timestamp structure that consists of year, month, day, hour, minute, second, and fractional seconds. The fractional seconds have a maximum scale of 7 digits. |
| DT_DECIMAL | An exact numeric value with a fixed precision and a fixed scale. This data type is a 12-byte value with a separate sign, a scale of 0 to 28, and a maximum precision of 29. |
| DT_EMPTY | A data type that does not have a value. |
| DT_FILETIME | A 64-bit value that represents the number of 100-nanosecond intervals since January 1, 1601. |
| DT_GUID | A globally unique identifier (GUID). |
| DT_I1 | A 1-byte, signed integer. |
| DT_I2 | A 2-byte, signed integer. |
| DT_I4 | A 4-byte, signed integer. |
| DT_I8 | An 8-byte, signed integer. |
| DT_IMAGE | A binary value with a maximum size of 231–1 (2,147,483,647) bytes. |
| DT_NTEXT | A Unicode character string with a maximum length of 2^30–1 (1,073,741,823) characters. |
| DT_NULL | A data type with a value of NULL. |
| DT_NUMERIC | An exact numeric value with a fixed precision and scale. This data type is a 16-byte value with a separate sign, a scale of 0 to 38, and a maximum precision of 38. |
| DT_R4 | A single-precision floating-point value. |
| DT_R8 | A double-precision floating-point value. |
| DT_STR | A null-terminated ANSI/MBCS character string. |
| DT_TEXT | An ANSI/MBCS character string with a maximum length of 231–1 (2,147,483,647) characters. |
| DT_UI1 | A 1-byte, unsigned integer. |
| DT_UI2 | A 2-byte, unsigned integer. |
| DT_UI4 | A 4-byte, unsigned integer. |
| DT_UI8 | An 8-byte, unsigned integer. |
| DT_WSTR | A null-terminated Unicode character string. |