What
is a File?
A file is a series of records stored or
saved in binary format. Relative data and information is stored or saved collectively
or as a group in file formats. A disk drive is formatted into numerous blocks
that can store or save records. File records are mapped onto those disk blocks.
What
is File Organization?
File Organization describes how file
records are mapped onto disk blocks.
Types of File Organization
to categorize file records:
Heap
File Organization: As soon as a file is
generated using Heap File Organization, the Operating System assigns memory
area to that files without any additional accounting details. File records can
be situated anywhere in that memory area. It is the duty of the software to
manage and maintain the records.
Sequential
File Organization: Each file record carries
a data field known as attribute to uniquely recognize that record. It is impossible to save
all the records in sequence in physical form. In sequential file organization, records are situated in the file in some sequential order based on the distinctive key field or search key.
Hash File
Organization: This makes uses of Hash function calculation
on some fields of the records. The result of the hash function decides the
location of disk block where the records are to be situated.
Clustered
File Organization: In Clutered File, related records from one
or more relations are kept in the same disk block, so that, the ordering of
records is not on the basis of primary key or search key.
What are
File Operations?
File operations are the procedures or processes made
on files database to insert, update, retrieve, alters, amend, and delete data
values on files.
What
are Update File Operations?
Update file operations are the
operations that amend the data values by insert, update or delete and so on.
What
are Retrieve File Operations?
Retrieval file operations do not alter
the data but retrieve them after non-compulsory conditional filtering.
What
is Open File Operation?
This can be defined as processes or procedures involved in opening of various files.
A file can be opened in read mode or write mode. In read mode, the operating system does not
allow anyone to alter or modify data. In write mode, data access and modification is allowed, so that Files opened in write mode can be read but cannot be shared.
What
is Locate File Operation?
This is the processes involved in the location of files. Every file has a file pointer, which states
the current position where the data is to be read or written. This pointer can
be amended accordingly and can be moved forward or
backward.
What
is Read File Operation?
The processes involved in making sure a file is readable or accessible but not modifiable.
By default, when files are opened in
read mode, the file pointer points to the beginning of the file.
What
is Write File Operation?
The processes involved in making sure a file is readable or accessible and modifiable.
User can select to open a file in write
mode, which enables them to edit its contents. It can be deletion, insertion,
or modification.
What
is Close File Operation?
The processes involved in making sure a file is appropriately closed. When a request to
close a file is generated, the operating system removes all the locks (if in
shared mode), saves the data (if altered) to the secondary storage media, and
releases all the buffers and file handlers associated with the file.
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