To a journey into the world of File Processing and Management. In this blog series, we’ll embark on an expedition through the essential techniques and tools for handling digital files effectively.
From organizing personal documents to managing data systems, file management is a vital skill in today’s digital landscape. Whether you’re a tech enthusiast or a professional seeking efficiency, this series offers practical insights and solutions.
Join us as we navigate through file organization techniques, explore diverse file formats, and uncover tools for seamless file processing. By the end, you’ll be equipped to conquer digital clutter and streamline your workflows.
So, let’s dive in together and discover the keys to mastering File Processing and Management. Happy exploring!
Introduction to File Processing & Management
In most applications, the file is the central element. Before data can be processed by a Computer-Based Information System (CBIS), it must be systematically organised. The most common method is to arrange data into fields, records, files and databases. Files can be considered to be the framework around which data processing revolves. The purpose of this unit is to look at the general concepts before going on to discuss the different methods of organising and accessing them.
Before we start to discuss file proper, here are basic things you should know first.
Elements of a File
A file consists of a number of records. Each record is made up of a number of fields and each field consists of a number of characters.
Logical Components of File
The logical components deal with the real-world objects the data represent. These are field, record and file. However, in today’s an information system, files most often exist as parts of database, or organised collections of interrelated data.
Field
A field is the basic element of data. An individual field contains a single value, such as an employee’s last name, a date, or the value of a sensor reading. It is characterised by its length and data type (e.g., ASCII, string, decimal). Depending on the file design, fields may be fixed length or variable length. In the latter case, the field often consists of two or three subfields: the actual value to be stored, the name of the field, and, in some cases, the length of the field. In other cases of variable-length fields, the length of the field is indicated by the use of special demarcation symbols between fields.
Record
A record is a collection of related fields that can be treated as a unit by some application program. For example, an employee record would contain such fields as name, identification number, job designation, date of employment, and so on. Again, depending on design, records may be of fixed length or variable length. A record will be of variable length if some of its fields are of variable length or if the number of fields may vary. In the latter case, each field is usually accompanied by a field name. In either case, the entire record usually includes a length field.
File
A file is a collection of related records. The file is treated as a single entity by users and applications and may be referenced by name. Files have names and may be created and deleted. Access control restrictions usually apply at the file level. That is, in a shared system, users and programs are granted or denied access to entire files. In some more
sophisticated systems, such controls are enforced at the record or even the field level.
File Naming
Files are abstraction mechanisms. They provide a way to store information and read it back later. This must be done in a way as to shield the user from the details of how and where the information is stored, and how the disks actually work. When a process creates a file, it gives the file a name. When the process terminates, the file continue to exist, and can be accessed by other processes using its name.
The exact rules for file naming vary somewhat from system to system, but all operating systems allow strings of one to eight letters as legal file names. The file name is chosen by the person creating it, usually to reflect its contents. There are few constraints on the format of the file name: It can comprise the letters A-Z, numbers 0-9 and special
characters $ # & + @ ! ( ) – { } ‘ ` _ ~ as well as space. The only symbols that cannot be used to identify a file are * | < > \ ^ = ? / [ ] ‘ ; , plus control characters. The main caveat on chosen a file name is that there are different rules for different operating systems that can present problems when files are moved from computer to another. For example,
Microsoft Windows is case insensitive, so files like MYEBOOKS, myebooks, MyEbooks are all the same to Microsoft Windows.
However, under the UNIX operating system, all three would be different files as, in this instance, file names are case sensitive.
Naming Convention
Usually a file would have two parts with “.” separating them. The part on the left side of the period character is called the main name while the part on the right side is called the extension. A good example of a file name is “course.doc.” The main name is course while the extension is doc. File extension differentiates between different types of files. We can have files with same names but different extensions and therefore we generally refer to a file with its name along with its extension and that forms a complete file name.
File Name Extension
A filename extension is a suffix to the name of a computer file applied to indicate the encoding convention or file format of its contents. In some operating systems (for example UNIX) it is optional, while in some others (such as DOS) it is a requirement. Some operating systems limit the length of the extension (such as DOS and OS/2, to three
characters) while others (such as UNIX) do not. Some operating systems (for example RISC OS) do not use file extensions. The following tables, which are extracted from Microsoft® Encarta (2007), show examples of some common filename extensions:
- PDF (Portable Document Format): Widely used for sharing documents that preserve the layout and formatting across different platforms and devices. Ideal for reports, manuals, and forms.
- JPEG/JPG (Joint Photographic Experts Group): Commonly used for digital images and photographs. JPEG files use compression to reduce file size while maintaining decent image quality, making them suitable for web and print.
- MP3 (MPEG Audio Layer III): Standard format for audio compression, popular for storing and playing music. MP3 files offer a good balance between sound quality and file size, making them ideal for digital music libraries and online streaming.
- MP4 (MPEG-4 Part 14): Versatile multimedia container format used for storing video, audio, and subtitles. MP4 files are widely compatible with various devices and platforms, making them suitable for sharing videos online and offline playback.
- DOC/DOCX (Microsoft Word Document): Native file format for Microsoft Word documents. DOCX is the newer version, offering enhanced features and compatibility. These files are commonly used for creating and sharing text-based documents, such as letters, essays, and reports.
- XLS/XLSX (Microsoft Excel Spreadsheet): Standard formats for spreadsheets created in Microsoft Excel. XLSX is the newer XML-based version with improved features and compatibility. These files are used for organizing and analyzing data, such as budgets, inventories, and financial statements.
- PNG (Portable Network Graphics): Lossless image format commonly used for graphics, illustrations, and logos. PNG files support transparent backgrounds and offer high-quality compression, making them suitable for web graphics and digital art.
- TXT (Plain Text): Simple file format consisting of unformatted text. TXT files are compatible with almost all text editors and platforms, making them ideal for storing plain text documents, such as notes, code snippets, and configuration files.
- GIF (Graphics Interchange Format): Image format that supports animation and short video clips. GIF files are widely used for creating memes, reactions, and simple animations for web content and social media.
- ZIP (Archive): Compressed file format used for bundling and reducing the size of multiple files and folders. ZIP files are commonly used for file backup, software distribution, and email attachments, as they help save storage space and facilitate easier file transfer.
File Attributes
The particular information kept for each file varies from operating system to operating system. No matter what operating system one might be using, files always have certain attributes or characteristics. Different file attributes are discussed as follow.
File Name
The symbolic file name is the only information kept in human-read form. As it is obvious, a file name helps users to differentiate between various files.
File Type
A file type is required for the systems that support different types of files. As discussed earlier, file type is a part of the complete file name.
We might have two different files; say “FileProcessing.doc” and “FileProcessing.txt”. Therefore the file type is an important attribute which helps in differentiating between files based on their types. File types indicate which application should be used to open a particular file.
Location
This is a pointer to the device and location on that device of the file. As it is clear from the attribute name, it specifies where the file is stored.
Size
Size attribute keeps track of the current size of a file in bytes, words or blocks. The size of a file is measured in bytes. A floppy disk holds about 1.44 Mb; a Zip disk holds 100 Mb or 250 Mb; a CD holds about 800Mb; a DVD holds about 4.7 Gb.
Protection
Protection attribute of a file keeps track of the access-control information that controls who can do reading, writing, executing, and so on.
Usage Count
This value indicates the number of processes that are currently using (have opened) a particular file.
Time, Date and Process Identification
This information may be kept for creation, last modification, and last use. Data provided by this attribute is often helpful for protection and usage monitoring. Each process has its own identification number which contains information about file hierarchy.
Attribute Values
In addition, all operating systems associate other information with each file. The list of attributes varies considerably from system to system.
The table below shows some of the possibilities, but other ones also exist. No existing system has all of these, but each is present in some system.
Fields and various attribute values