The RAW data type
ORACLE supports the RAW data type to hold binary data. This data type is
for example used to return values from the SYS_GUID() SQL function.
Solution
The ORACLE RAW values can be converted to a character string in the hexadecimal
notation.
When fetching rows from the database, the database driver will automatically convert ORACLE
RAW values to hexadecimal. On the other hand, when using SQL parameters, the
database driver will convert hexadecimal VARCHAR strings to binary data.
Since each byte is represented with two characters in the hexadecimal notation, you must
define a VARCHAR(N*2) variable to hold the values of a native
RAW(N) column.
When extracting a database schema with the fgldbsch tool, the ORACLE
RAW(N) type is converted to VARCHAR2(N*2).