does it support CLOBs/BLOBs in PL/SQL?
The answer is: it depends. You need to keep in mind that “CLOB/BLOB” as a PL/SQL data type is a locator of a large object, not a value. That is, the object itself needs to be created first, its locator needs to be retrieved from the database into C++, and only then the locator can be passed into PL/SQL. Also, see code example 378.