WORKAROUND
You can import long text using the following workaround:
DECLARE
v_clob CLOB;
c_text CLOB;
begin
c_text := 'Very loooooooooong text.'
INSERT INTO TABLE_NAME (ID, LONG_TEXT)
VALUES (1, EMPTY_CLOB())
RETURNING long_text INTO v_clob;
DBMS_LOB.write(v_clob,dbms_lob.getlength(c_text),1,c_text);
commit;
end;
STATUS
Waiting for a fix in a future version of Toad for Oracle
