国产av日韩一区二区三区精品,成人性爱视频在线观看,国产,欧美,日韩,一区,www.成色av久久成人,2222eeee成人天堂

Home Backend Development PHP Tutorial How to Create a Unique 64bit Integer from String

How to Create a Unique 64bit Integer from String

Feb 20, 2025 pm 12:15 PM

PHP's built-in md5() function generates 32-character hexadecimal strings, useful for creating fingerprints. However, generating unique 64-bit integer fingerprints from URLs requires a different approach, especially when dealing with database indexing efficiency. This article details a solution for creating these unique IDs, focusing on URL canonization and efficient 64-bit integer conversion.

How to Create a Unique 64bit Integer from String

Key Considerations:

  • URL Canonization: Different URLs can point to the same page (e.g., variations in query parameters). Canonization creates a consistent representation, ensuring identical pages have identical IDs. This involves removing the protocol and ignoring fragments after the hashmark (#).
  • 64-bit Integer Conversion: PHP's inherent limitations with 64-bit integers necessitate the use of the GMP library for reliable conversion.

The Challenge: Efficiently assigning unique 64-bit integer IDs to web pages for dynamic widget development, avoiding inefficient text-based indexing of URLs.

Solution Breakdown:

  1. URL Canonization: The provided canonizeUrl() function standardizes URLs. It lowercases the URL, extracts the host and path, and processes the query string. The canonizeQueryString() function sorts query parameters lexicographically for consistency, handling duplicate parameters and applying RFC 3986-compliant URL encoding.

  2. String to Int64 Conversion: The get64BitHash() function utilizes the GMP library to convert the canonized URL into a 64-bit integer. It takes the first 16 characters of the MD5 hash (for efficiency) and interprets them as a hexadecimal number.

  3. Combined Function: The urlTo64BitHash() function combines the above steps, providing a complete solution: canonize the URL then convert it to a 64-bit integer hash.

Code Examples:

(The code examples for canonizeUrl(), canonizeQueryString(), urlencode_rfc3986(), and get64BitHash() remain the same as in the original input.)

Performance and Collision Testing: Tests with 10,000,000 iterations showed an average generation time of 460 milliseconds per 100,000 URLs and no collisions were detected (using Intel i3, Windows 7 64-bit, PHP 5.3).

Conclusion: This approach provides a robust and efficient method for generating unique 64-bit integer IDs from URLs, suitable for applications requiring efficient database indexing and unique identifier generation. The use of GMP overcomes PHP's limitations and the URL canonization ensures consistency.

Frequently Asked Questions (FAQs): (The FAQs section remains largely the same as in the original input, with minor wording adjustments for clarity and consistency.)

The above is the detailed content of How to Create a Unique 64bit Integer from String. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undress AI Tool

Undress AI Tool

Undress images for free

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

What are some best practices for versioning a PHP-based API? What are some best practices for versioning a PHP-based API? Jun 14, 2025 am 12:27 AM

ToversionaPHP-basedAPIeffectively,useURL-basedversioningforclarityandeaseofrouting,separateversionedcodetoavoidconflicts,deprecateoldversionswithclearcommunication,andconsidercustomheadersonlywhennecessary.StartbyplacingtheversionintheURL(e.g.,/api/v

How do I implement authentication and authorization in PHP? How do I implement authentication and authorization in PHP? Jun 20, 2025 am 01:03 AM

TosecurelyhandleauthenticationandauthorizationinPHP,followthesesteps:1.Alwayshashpasswordswithpassword_hash()andverifyusingpassword_verify(),usepreparedstatementstopreventSQLinjection,andstoreuserdatain$_SESSIONafterlogin.2.Implementrole-basedaccessc

What are the differences between procedural and object-oriented programming paradigms in PHP? What are the differences between procedural and object-oriented programming paradigms in PHP? Jun 14, 2025 am 12:25 AM

Proceduralandobject-orientedprogramming(OOP)inPHPdiffersignificantlyinstructure,reusability,anddatahandling.1.Proceduralprogrammingusesfunctionsorganizedsequentially,suitableforsmallscripts.2.OOPorganizescodeintoclassesandobjects,modelingreal-worlden

What are weak references (WeakMap) in PHP, and when might they be useful? What are weak references (WeakMap) in PHP, and when might they be useful? Jun 14, 2025 am 12:25 AM

PHPdoesnothaveabuilt-inWeakMapbutoffersWeakReferenceforsimilarfunctionality.1.WeakReferenceallowsholdingreferenceswithoutpreventinggarbagecollection.2.Itisusefulforcaching,eventlisteners,andmetadatawithoutaffectingobjectlifecycles.3.YoucansimulateaWe

How can you handle file uploads securely in PHP? How can you handle file uploads securely in PHP? Jun 19, 2025 am 01:05 AM

To safely handle file uploads in PHP, the core is to verify file types, rename files, and restrict permissions. 1. Use finfo_file() to check the real MIME type, and only specific types such as image/jpeg are allowed; 2. Use uniqid() to generate random file names and store them in non-Web root directory; 3. Limit file size through php.ini and HTML forms, and set directory permissions to 0755; 4. Use ClamAV to scan malware to enhance security. These steps effectively prevent security vulnerabilities and ensure that the file upload process is safe and reliable.

What are the differences between == (loose comparison) and === (strict comparison) in PHP? What are the differences between == (loose comparison) and === (strict comparison) in PHP? Jun 19, 2025 am 01:07 AM

In PHP, the main difference between == and == is the strictness of type checking. ==Type conversion will be performed before comparison, for example, 5=="5" returns true, and ===Request that the value and type are the same before true will be returned, for example, 5==="5" returns false. In usage scenarios, === is more secure and should be used first, and == is only used when type conversion is required.

How can you interact with NoSQL databases (e.g., MongoDB, Redis) from PHP? How can you interact with NoSQL databases (e.g., MongoDB, Redis) from PHP? Jun 19, 2025 am 01:07 AM

Yes, PHP can interact with NoSQL databases like MongoDB and Redis through specific extensions or libraries. First, use the MongoDBPHP driver (installed through PECL or Composer) to create client instances and operate databases and collections, supporting insertion, query, aggregation and other operations; second, use the Predis library or phpredis extension to connect to Redis, perform key-value settings and acquisitions, and recommend phpredis for high-performance scenarios, while Predis is convenient for rapid deployment; both are suitable for production environments and are well-documented.

How do I perform arithmetic operations in PHP ( , -, *, /, %)? How do I perform arithmetic operations in PHP ( , -, *, /, %)? Jun 19, 2025 pm 05:13 PM

The methods of using basic mathematical operations in PHP are as follows: 1. Addition signs support integers and floating-point numbers, and can also be used for variables. String numbers will be automatically converted but not recommended to dependencies; 2. Subtraction signs use - signs, variables are the same, and type conversion is also applicable; 3. Multiplication signs use * signs, which are suitable for numbers and similar strings; 4. Division uses / signs, which need to avoid dividing by zero, and note that the result may be floating-point numbers; 5. Taking the modulus signs can be used to judge odd and even numbers, and when processing negative numbers, the remainder signs are consistent with the dividend. The key to using these operators correctly is to ensure that the data types are clear and the boundary situation is handled well.

See all articles