EMPTY_BLOB and EMPTY_CLOB return an empty LOB locator that can be used to initialize a LOB variable or, in an INSERT or UPDATE statement, to initialize a LOB column or attribute to EMPTY. EMPTY means that the LOB is initialized, but not populated with data.
UPDATE print_media SET ad_photo = EMPTY_BLOB();
OCI operation LOB column first use empty_blob, empty_clob initialize the LOB column.
if not initialize the LOB column get error ORA-01405:fetched column value is NULL.
BFILENAME is initialize for BFILE datatype.
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