If you try to obtain a CHAR, VARCHAR, or RAW column as a data stream without redefining the column type, OceanBase Connector/J returns a Java InputStream but does not actually transmit the stream.
For these data types, OceanBase Connector/J extracts all data into an in-memory buffer when it calls the executeQuery or next method. The entry point of the getXXXStream method returns the streams that read data from the buffer.