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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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