Oracle C++ Call Interface Programmer's Guide

External Datatypes
FLOAT
The external datatype FLOAT processes numbers with fractional parts. The number
is represented in the host system’s floating-point format. Normally, the length is 4
or 8 bytes.
The internal format of an Oracle number is decimal. Most floating-point
implementations are binary. Oracle, therefore, represents numbers with greater
precision than floating-point representations.
INTEGER
The external datatype INTEGER is used for converting numbers. An external integer
is a signed binary number. Its size is operating system-dependent. If the number
being returned from Oracle is not an integer, then the fractional part is discarded,
and no error is returned. If the number returned exceeds the capacity of a signed
integer for the system, then Oracle returns an overflow on conversion error.
Note: A rounding error may occur when converting between
FLOAT and NUMBER. Using a FLOAT as a bind variable in a query
may return an error. You can work around this by converting the
FLOAT to a string and using the OCCI type OCCI_SQLT_CHR or
the OCCI type OCCI_SQLT_STR for the operation.
INTERVAL DAY TO SECOND
The external datatype INTERVAL DAY TO SECOND stores the difference between two
datetime values in terms of days, hours, minutes, and seconds. Specify this datatype
as follows:
INTERVAL DAY [(day_precision)]
TO SECOND [(fractional_seconds_precision)]
This example uses the following placeholders:
■ day_precision: Number of digits in the DAY datetime field. Accepted values
are 1 to 9. The default is 2.
■ fractional_seconds_precision: Number of digits in the fractional part of
the SECOND datetime field. Accepted values are 0 to 9. The default is 6.
To specify an INTERVAL DAY TO SECOND literal with nondefault day and second
precisions, you must specify the precisions in the literal. For example, you might
Datatypes 4-11