ThinkPHP is one of the more popular PHP frameworks currently and is widely used, especially in Web back-end development. When using ThinkPHP to develop applications, we often need to query and count data in the database. This article will introduce the query counting of ThinkPHP5 in detail.
1. Query
In ThinkPHP5, we can query the database through the Db
class or the Model
class. Here we take the Model
class as an example.
- Basic query
We can implement basic query operations through the select()
method, as follows:
//创建模型对象 $user = new UserModel(); //查询user表中姓名为张三的记录 $result = $user -> where('name','张三') -> select();
The above code , the where()
method is used to specify query conditions, and its parameter format is where(query field, query value)
. When the query conditions are multiple fields, we can use chain operations.
is as follows:
$user -> where('name','张三') -> where('age',20) -> select();
This means querying the records in the user table whose name is Zhang San and whose age is 20.
- Conditional query
We can add where()
, whereOr()
, to the query statement whereLike()
and other conditional query methods to achieve more flexible query operations.
is as follows:
//查询user表中年龄大于20,且性别为男的记录 $result = $user -> where('age','>',20) -> where('gender','男') -> select(); //查询user表中年龄小于20或性别为女的记录 $result = $user -> where('age',' whereOr('gender','女') -> select(); //查询user表中姓名包含‘张’的记录 $result = $user -> whereLike('name','%张%') -> select();
In the above code, the where()
method and the whereOr()
method respectively indicate that the query conditions are "and" and The "or" relationship has the same parameter format; the whereLike()
method is used to implement fuzzy query, and its second parameter represents the query matching condition.
In addition, we can also chain call order()
to sort the query results, as follows:
$result = $user -> where('age','>',20) -> order('age desc') -> select();
The above code means to query the records whose age is greater than 20 in the user table. And sorted by age from oldest to youngest.
- Paging query
When we need to query a large amount of data, we can use the paging query function to prevent the server from being overloaded due to excessive data volume.
In ThinkPHP5, we can use the limit()
method to implement paging query. limit()
The method has two parameters. The first parameter indicates the starting offset, and the second parameter indicates the number of records displayed on each page.
is as follows:
// 每页显示3条记录,查询第2页的数据 $result = $user -> limit(3,3) -> select();
The above code indicates querying page 2 of the user table and displaying 3 records on each page.
2. Counting
In ThinkPHP5, we can implement the basic counting function through the count()
method.
is as follows:
//计算user表中记录总数 $count = $user -> count(); //计算user表中年龄大于20的记录数 $count = $user -> where('age','>',20) -> count();
It should be noted that the count()
method actually performs a query on the database, so in actual applications, errors should be minimized as much as possible. Necessary counting operations to improve application performance.
3. Summary
In ThinkPHP5, we can implement database query and counting function. When using it, you should pay attention to the reasonable use of query conditions and paging query functions, and minimize unnecessary counting operations to improve application performance.
The above is the detailed content of Detailed explanation of how thinkphp5 implements query counting function. For more information, please follow other related articles on the PHP Chinese website!

This article compares Lenovo's ThinkBook and ThinkPad laptop lines. ThinkPads prioritize durability and performance for professionals, while ThinkBooks offer a stylish, affordable option for everyday use. The key differences lie in build quality, p

This article explains how to prevent SQL injection in ThinkPHP applications. It emphasizes using parameterized queries via ThinkPHP's query builder, avoiding direct SQL concatenation, and implementing robust input validation & sanitization. Ad

This article addresses ThinkPHP vulnerabilities, emphasizing patching, prevention, and monitoring. It details handling specific vulnerabilities via updates, security patches, and code remediation. Proactive measures like secure configuration, input

This article details ThinkPHP software installation, covering steps like downloading, extraction, database configuration, and permission verification. It addresses system requirements (PHP version, web server, database, extensions), common installat

This tutorial addresses common ThinkPHP vulnerabilities. It emphasizes regular updates, security scanners (RIPS, SonarQube, Snyk), manual code review, and penetration testing for identification and remediation. Preventative measures include secure

This guide details database connection in ThinkPHP, focusing on configuration via database.php. It uses PDO and allows for ORM or direct SQL interaction. The guide covers troubleshooting common connection errors, managing multiple connections, en

This article demonstrates building command-line applications (CLIs) using ThinkPHP's CLI capabilities. It emphasizes best practices like modular design, dependency injection, and robust error handling, while highlighting common pitfalls such as insu

This article introduces ThinkPHP, a free, open-source PHP framework. It details ThinkPHP's MVC architecture, features (routing, database interaction), advantages (rapid development, ease of use), and disadvantages (potential over-engineering, commun


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

MantisBT
Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft

Notepad++7.3.1
Easy-to-use and free code editor

Atom editor mac version download
The most popular open source editor
