(Thanks to Mark Piermarini for the Java bit here....)

Ok, here we go. first I generated a test set of data in C:

#include "stdio.h"

void main()
{
float x = 1.123;
double y = 12121;
FILE * output;

output = fopen( "test.dat", "wb" );
fwrite( &x, 1, sizeof(x), output );
fwrite( &y, 1, sizeof(y), output );
fclose(output );
}


then, i loaded that up in the database:

create or replace directory my_files as '/export/home/tkyte'
/

drop table t;

create table t ( x blob );

declare
l_bfile bfile;
l_blob blob;
begin
l_bfile := bfilename( 'MY_FILES', 'test.dat' );
dbms_lob.fileopen( l_bfile );

insert into t values ( empty_blob() ) returning x into l_blob;

dbms_lob.loadfromfile( l_blob, l_bfile, dbms_lob.getlength(l_bfile) );
dbms_lob.fileclose( l_bfile );
end;
/


and then:


ops$tkyte@DEV816> create or replace and compile java source
2 named "RawIEEE" as
3 import oracle.sql.*;
4
5 public class RawIEEE {
6 static public NUMBER rawFloatToNUMBER(RAW r) throws Exception {
7 return new NUMBER(
8 Float.intBitsToFloat(
9 Integer.parseInt(r.stringValue(), 16)
10 )
11 );
12 }
13
14 static public NUMBER rawDoubleToNUMBER(RAW r) throws Exception {
15 return new NUMBER(
16 Double.longBitsToDouble(
17 Long.parseLong(r.stringValue(), 16)
18 )
19 );
20 }
21 }
22 /

Java created.

ops$tkyte@DEV816> show errors
No errors.
ops$tkyte@DEV816>
ops$tkyte@DEV816> create or replace function
2 RAW_FLOAT_TO_NUMBER(p_raw in RAW) return NUMBER
3 as language java
4 name 'RawIEEE.rawFloatToNUMBER(oracle.sql.RAW) return
5 oracle.sql.NUMBER';
6 /

Function created.

ops$tkyte@DEV816>
ops$tkyte@DEV816> create or replace function
2 RAW_DOUBLE_TO_NUMBER(p_raw in RAW) return NUMBER
3 as language java
4 name 'RawIEEE.rawDoubleToNUMBER(oracle.sql.RAW) return
5 oracle.sql.NUMBER';
6 /

Function created.



And now I can simply:

ops$tkyte@DEV816> column rfloat format a8
ops$tkyte@DEV816> column rdouble format a16
ops$tkyte@DEV816>
ops$tkyte@DEV816> select dbms_lob.substr( x, 4, 1 ) rfloat,
2 RAW_FLOAT_TO_NUMBER(dbms_lob.substr( x, 4 , 1)) xfloat,
3 dbms_lob.substr( x, 8, 5 ) rdouble,
4 RAW_DOUBLE_TO_NUMBER(dbms_lob.substr( x, 8, 5)) xdouble
5 from t
6 /

RFLOAT XFLOAT RDOUBLE XDOUBLE
-------- ---------- ---------------- ----------
3F8FBE77 1.123 40C7AC8000000000 12121