How can hashing help you optimize data storage?

Hashing is a powerful tool widely used in various areas of IT: from protecting passwords to creating fast data structures. In this article, we'll take a closer look at how hashing can help optimize data storage, eliminate duplicates, and improve file handling.

Hashing is the process of converting data into a unique, fixed string identifier called a hash. Hash functions such as MD5, SHA-1 And SHA-256, apply certain algorithms to the input data and generate a fixed-length string. These functions have many useful properties: they are deterministic (the same input data always produces the same hash), fast, and hard to invert (it is impossible to reconstruct the original data from the hash). These properties make hashing an ideal tool for a variety of tasks, including data storage optimization.

An example of such a transformation:

import hashlib

# Пример строки
example_string = "Hello, World!"

# MD5
md5_hash = hashlib.md5(example_string.encode()).hexdigest()
print(f"MD5: {md5_hash}")

# SHA-1
sha1_hash = hashlib.sha1(example_string.encode()).hexdigest()
print(f"SHA-1: {sha1_hash}")

# SHA-256
sha256_hash = hashlib.sha256(example_string.encode()).hexdigest()
print(f"SHA-256: {sha256_hash}")

As a result we get:

$ py hashing_example.py 
MD5: 65a8e27d8879283831b664bd8b7f0ad4
SHA-1: 0a0a9f2a6772942557ab5355d76af442f8f65e01
SHA-256: dffd6021bb2bd5b0af676290809ec3a53191dd81c7f70a4b28688a362182986f

File hashing

One of the most interesting and accessible ways to optimize storage is file hashing. The process of file hashing converts file data into a unique string identifier. This provides the following benefits:

1. Eliminating duplicates
   Hashing makes it easy to determine if two files are the same. If two files have the same hash, they are identical. This helps avoid storing duplicates and saves space.

2. Optimization of working with data
   Storing hashes instead of files simplifies and speeds up many operations, such as checking data integrity, searching and matching files. Hashing reduces the amount of data that needs to be manipulated directly, which speeds up the processing time.

3. Accelerate data backup and recovery
   When backing up data, using hashes helps identify changed files. This allows you to copy only changed or new files, speeding up the backup process.

4. Safety
   Hashing helps protect data from unauthorized access and changes. Any change to a file will change its hash, allowing tampering to be quickly detected.

Implementation

Implementing file hashing is very simple. Here is a clear example of Implementing file hashing on Python using the library hashlib:

import hashlib


def get_file_hash(file_path):
    hasher = hashlib.sha256()
    with open(file_path, 'rb') as file:
        buffer = file.read()
        hasher.update(buffer)
    return hasher.hexdigest()


file_path="example_file.txt"
file_hash = get_file_hash(file_path)
print(f'Hash for {file_path}: {file_hash}')

This code calculates a SHA-256 hash for the specified file, by which the file can be uniquely identified. Similar functions can be implemented in other programming languages.

Already at the stage of uploading files to your server, you can prevent duplication by checking the presence of the received hash in the list of already stored values. Thus, you can leave only one of the files, replacing the entire media object with a link to the original.

And so once again we can be convinced that hashing is a powerful and useful tool that is used in a variety of areas when working with data. Implementing this technology will help you achieve significant improvements in data management, making your file work more organized and efficient.

I write even more about working with data, storing and managing it in my telegram channel Econet, which is dedicated to the project of the same name, where I study, reflect and look for the best solutions to the problems of working with data and optimizing it. I will be very grateful for your criticism and suggestions, because I myself am just studying this field and want to contribute to the improvement of our digital world, where we all live right now.