Oracle® Database SQL Language Reference 11g Release 2 (11.2) Part Number E1059204 


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Syntax
Purpose
TO_BINARY_FLOAT
returns a singleprecision floatingpoint number.
expr
can be a character string or a numeric value of type NUMBER
, BINARY_FLOAT
, or BINARY_DOUBLE
. If expr
is BINARY_FLOAT
, then the function returns expr
.
The optional 'fmt
' and 'nlsparam
' arguments are valid only if expr
is a character string. They serve the same purpose as for the TO_CHAR
(number) function.
The incasesensitive string 'INF
' is converted to positive infinity.
The incasesensitive string 'INF
' is converted to negative identity.
The incasesensitive string 'NaN
' is converted to NaN
(not a number).
You cannot use a floatingpoint number format element (F
, f
, D
, or d
) in a character string expr
.
Conversions from character strings or NUMBER
to BINARY_FLOAT
can be inexact, because the NUMBER
and character types use decimal precision to represent the numeric value and BINARY_FLOAT
uses binary precision.
Conversions from BINARY_DOUBLE
to BINARY_FLOAT
are inexact if the BINARY_DOUBLE
value uses more bits of precision than supported by the BINARY_FLOAT
.
Examples
Using table float_point_demo
created for TO_BINARY_DOUBLE, the following example converts a value of data type NUMBER
to a value of data type BINARY_FLOAT
:
SELECT dec_num, TO_BINARY_FLOAT(dec_num) FROM float_point_demo; DEC_NUM TO_BINARY_FLOAT(DEC_NUM)   1234.56 1.235E+003