What is Bfile data type in Oracle?
BFILE is an Oracle proprietary data type that provides read-only access to data located outside the database tablespaces on tertiary storage devices, such as hard disks, network mounted files systems, CD-ROMs, PhotoCDs, and DVDs. BFILE data is not under transaction control and is not stored by database backups.
What is the purpose of Bfile?
BFILENAME () is a built-in function that is used to initialize the BFILE column to point to the external file. Once physical files are associated with records using SQL DML, subsequent read operations on the BFILE can be performed using PL/SQL DBMS_LOB package and OCI.
What is a Bfile locator?
The BFILE datatype is used to act as a pointer or locator for the actual external data files.
Where are data files stored in Oracle?
Most Oracle databases store files in a file system, which is a data structure built inside a contiguous disk address space. All operating systems have file managers that allocate and deallocate disk space into files within a file system.
What is difference between blob and Bfile?
Blobs are in the database and all of the features of the database are available. A bfile is a file in the OS, outside the database.
What is a blob in Oracle?
A BLOB (binary large object) is a varying-length binary string that can be up to 2,147,483,647 characters long. Like other binary types, BLOB strings are not associated with a code page. In addition, BLOB strings do not hold character data.
Which of the following describes a Bfile data type?
BFILE is a data type that points to an external file, which limits its maximum size to 2 GB.
What is raw data type in Oracle?
RAW. The RAW datatype is used for binary data or byte strings that are not to be interpreted by Oracle, for example, to store graphics character sequences. The maximum length of a RAW column is 2000 bytes.
What happens when tablespace is offline?
When a tablespace is taken offline, the database takes all the associated files offline. You cannot take the following tablespaces offline: SYSTEM.
What is system tablespace in Oracle 10g database?
SYSTEM – a tablespace that is always used to store SYSTEM data that includes data about tables, indexes, sequences, and other objects – this metadata comprises the data dictionary. Every Oracle database has to have a SYSTEM tablespace—it is the first tablespace created when a database is created.
What is Nclob datatype in Oracle?
NCLOB (National Character Large Object) is an Oracle data type that can hold up to 4 GB of character data. It’s similar to a CLOB, but characters are stored in a NLS or multibyte national character set.
What is Oracle subtype?
From the Oracle version 7.1, the system allows us to create a special data type called as subtypes over the existing predefined or user defined data types. A subtype does not create a new data type rather a derived formed by the base type. A subtype may or may not constrain the values allowed by the base data type.
What are raw data types?
The RAW datatype is used for binary data or byte strings that are not to be interpreted by Oracle, for example, to store graphics character sequences. The maximum length of a RAW column is 2000 bytes.
What is Nclob datatype?
Examples. NCLOB (National Character Large Object) is an Oracle data type that can hold up to 4 GB of character data. It’s similar to a CLOB, but characters are stored in a NLS or multibyte national character set.
How do I know if tablespace is online or offline?
Check status of tablespace offline or online in Oracle Check the tablespace status is offline or online. SELECT TABLESPACE_NAME,STATUS FROM DBA_TABLESPACES; Take the tablespace offline.
Which tablespace Cannot be taken offline?
You cannot take the following tablespaces offline: SYSTEM. The undo tablespace. Temporary tablespaces.