Course Introduction：This tutorial explores in-depth how to accurately determine whether specific data exists in the MongoDB Atlas database when using the PHP MongoDB driver. We will correct normal errors, that is, confusing query definitions and query results, and provide a correct verification method based on cursor processing to ensure that the logic of data existence check is rigorous and effective, and avoid logical errors caused by misunderstanding of the query return value.
2025-08-26 comment 0 374
Course Introduction：How to Retrieve MySQL Database "Schema" Names Using Java JDBCIn Java, the getSchemas() method of the DatabaseMetaData class is typically used to...
2024-10-31 comment 0 419
Course Introduction：To implement exporting data as an Excel or CSV file in Laravel, the most efficient way is to use the maatwebsite/excel package. 1. Install the LaravelExcel package: run composerrequiremaatwebsite/excel, and optionally publish configuration files. 2. Create an export class: Use phpartisanmake:exportUsersExport--model=User to generate the export class, and define the data query in the collection method, and set the header in the headings method. 3. Create controller and route: Generate ExportController and
2025-07-24 comment 0 142
Course Introduction：Delayed static binding in PHP: flexible database queries Lazy static binding (LSB) is a feature in PHP that allows a subclass to reference a static property or method of its parent class using the static keyword. This makes it possible to implement dynamic behavior in classes, which is especially useful in inheritance and subclass functionality customization. The core of delayed static binding lies in the use of the static keyword: when the PHP interpreter encounters the static attribute when compiling a function, it will delay determining its value until runtime. The value ultimately comes from the class that calls the function. Application scenario: dynamic database query Suppose you are developing a web application with a database. You have a Database base class that contains the methods for interacting with the database
2025-01-16 comment 0 850
Course Introduction：Can I Include Code into a PHP Class?Question: Is it possible to include an external file containing method definitions into a PHP class?Answer:...
2024-11-26 comment 0 866
Course Elementary 13891
Course Introduction：Scala Tutorial Scala is a multi-paradigm programming language, designed to integrate various features of object-oriented programming and functional programming.
Course Elementary 82444
Course Introduction："CSS Online Manual" is the official CSS online reference manual. This CSS online development manual contains various CSS properties, definitions, usage methods, example operations, etc. It is an indispensable online query manual for WEB programming learners and developers! CSS: Cascading Style Sheets (English full name: Cascading Style Sheets) is an application used to express HTML (Standard Universal Markup Language).
Course Elementary 13237
Course Introduction：SVG is a markup language for vector graphics in HTML5. It maintains powerful drawing capabilities and at the same time has a very high-end interface to operate graphics by directly operating Dom nodes. This "SVG Tutorial" is intended to allow students to master the SVG language and some of its corresponding APIs, combined with the knowledge of 2D drawing, so that students can render and control complex graphics on the page.
Course Elementary 24695
Course Introduction：In the "AngularJS Chinese Reference Manual", AngularJS extends HTML with new attributes and expressions. AngularJS can build a single page application (SPAs: Single Page Applications). AngularJS is very easy to learn.
Course Elementary 27541
Course Introduction：Go is a new language, a concurrent, garbage-collected, fast-compiled language. It can compile a large Go program in a few seconds on a single computer. Go provides a model for software construction that makes dependency analysis easier and avoids most C-style include files and library headers. Go is a statically typed language, and its type system has no hierarchy. Therefore users do not need to spend time defining relationships between types, which feels more lightweight than typical object-oriented languages. Go is a completely garbage-collected language and provides basic support for concurrent execution and communication. By its design, Go is intended to provide a method for constructing system software on multi-core machines.
The oci_parse() method returns null parsing method
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Best way to handle transactions efficiently using Promises
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