You issue this command to create a table called LOB_STORE:
CREATE TABLE lob_store
(lob_id NUMBER(3),
photo BLOB DEFAULT EMPTY_BLOB(),
cv CLOB DEFAULT NULL,
ext_file BFILE DEFAULT NULL)
/
What is the outcome?
A.
The table is created successfully.
B.
It generates an error because DEFAULT cannot be set to EMPTY_BLOB() during table
creation.
C.
It generates an error because DEFAULT cannot be set to null for a CLOB column during table
creation.
D.
It generates an error because DEFAULT cannot be set to null for a BFILE column during table
creation.
A
SQL> CREATE TABLE LOBSTORE (
16:18:56 2 LOB_ID NUMBER(3),
16:19:07 3 PHOTO BLOB DEFAULT EMPTY_BLOB(),
16:19:21 4 CV CLOB DEFAULT NULL,
16:19:33 5 EXT_FILE BFILE DEFAULT NULL
16:19:48 6 );
Table created.
Elapsed: 00:00:00.12
B
EMPTY_BLOB IS callable through its package,,, dbms_blob.enply:blob()
OPS not
it’s defined in the standard package
function EMPTY_CLOB return clob;
function EMPTY_BLOB return blob;
function BFILENAME(directory varchar2,filename varchar2) return BFILE;
so…………… A
A.
Output: Table created.
English:
https://translate.google.com/translate?hl=es&sl=es&tl=en&u=http%3A%2F%2Fwww.oracle.com%2Ftechnetwork%2Fes%2Farticles%2Fsql%2Fmanejo-de-oracle-large-objects-1937051-esa.html
Management Oracle Large Objects (LOB)
Oracle recommends that you initialize a CLOB field with a LOB Locator empty and not leave it as NULL. To do this we can do by EMPTY_CLOB () function from the table creation or after, for example:
SQL> create table TABLA_BLOB (id number, valor BLOB default EMPTY_BLOB());
Table created
SQL> alter table TABLA_BLOB modify valor default EMPTY_BLOB();
Tabl altered
Manejo de Oracle Large Objects (LOB)
Oracle recomienda que inicialicemos un campo BLOB con un LOB Locator vacio y no dejarlo como NULL.
La función EMPTY_BLOB nos ayuda en este propósito, por ejemplo:
SQL> create table TABLA_BLOB (id number, valor BLOB default EMPTY_BLOB());
Table created
SQL> alter table TABLA_BLOB modify valor default EMPTY_BLOB();
Tabl altered
oracle.com/technetwork/es/articles/sql/manejo-de-oracle-large-objects-1937051-esa.html