Purpose
EMPTY_BLOB() returns an empty BLOB locator. The locator is not NULL, and the LOB length is 0.
Syntax
EMPTY_BLOB()
Return type
The return type is BLOB.
Examples
The following example returns an empty BLOB locator and checks whether the locator is NULL and the length of the LOB:
obclient> SELECT CASE WHEN EMPTY_BLOB() IS NULL THEN 'NULL' ELSE 'NOT NULL' END AS blob_is_null,
DBMS_LOB.GETLENGTH(EMPTY_BLOB()) AS blob_len
FROM DUAL;
+--------------+----------+
| BLOB_IS_NULL | BLOB_LEN |
+--------------+----------+
| NOT NULL | 0 |
+--------------+----------+
1 row in set