Home Database Mysql Tutorial MySQL中的C API

MySQL中的C API

Jun 07, 2016 pm 03:52 PM
api mysql

#include my_global.h#include mysql.hint main(int argc, char **argv){ MYSQL *conn; MYSQL_RES *result; MYSQL_ROW row; int num_fields; int i; conn = mysql_init(NULL); mysql_real_connect(conn, localhost, user, passwd, test, 0, NULL, 0); mysql_

#include <my_global.h>
#include <mysql.h>
int main(int argc, char **argv)
{
  MYSQL *conn;
  MYSQL_RES *result;
  MYSQL_ROW row;
  int num_fields;
  int i;

  conn = mysql_init(NULL);
  mysql_real_connect(conn, "localhost", "user", "passwd", "test", 0, NULL, 0);
  mysql_query(conn, "select * from student");
  result = mysql_store_result(conn);
  num_fields = mysql_num_fields(result);
  while ((row = mysql_fetch_row(result)))
  {
      for(i = 0; i <br>
注释:
<p>MYSQL* conn;</p>
conn = mysql_init(NULL);<br>
初始化一个MYSQL结构体,这个结构体就是一个数据库连接句柄。<br>
<p><br>
</p>
<p>mysql_real_connect(conn, "localhost", "user", '"passwd", "test", 0, NULL, 0) ;<br>
</p>
<p>建立一个到mysql数据库的链接。函数参数 链接句柄、主机名、用户、密码、数据库名、端口、unix套接字和客户端标志。<br>
</p>
<p><br>
</p>
<p>mysql_query(conn, "create database testdb");</p>
<p>mysql_query执行指定为“以Null终结的字符串”的SQL查询。<br>
</p>
<p><br>
</p>
<p>MYSQL_RES *result;<br>
</p>
<p>result = mysql_store_result(conn);<br>
</p>
<p>检索完整的结果集至客户端。<br>
</p>
<p><br>
</p>
<p>MYSQL_ROW row;</p>
<p>row = mysql_fetch_row(result)<br>
</p>
<p>获取结果集中的一行</p>
<p> </p>
<p>mysql_num_fields(result);<br>
</p>
<p>返回结果集中的列数</p>
<p><br>
</p>
<p>for(i = 0; i 
</p>
<p>printf("%s ", row[i] ? row[i] : "NULL");</p>
<p>}<br>
</p>
<p>输出一行数据</p>
<p><br>
</p>
<p>mysql_close(conn);<br>
<br>
关闭数据库链接。<br>
</p>
<p><br>
</p>
<p>printf("Error %u: %s\n", mysql_errno(conn), mysql_error(conn));<br>
</p>
<p>错误处理。mysql_errno返回上次调用的MySQL函数的错误编号。</p>
<p>mysql_error返回上次调用的MySQL函数的错误消息。</p>
<p><br>
</p>
<p>除非作了其他规定,返回指针的函数将返回非Null值,以指明成功,或返回NULL值以指明出错。</p>
<p>返回整数的函数将返回0以指明成功,或返回非0值以指明出错。注意,非0值仅表明这点。</p>
<p>除非在函数描述中作了其他说明,不要对非0值进行测试:<br>
if (result)                   /* correct */<br>
    ... error ...</p>
<p><br>
if (result 
    ... error ...<br>
 <br>
if (result == -1)             /* incorrect */<br>
</p>
<p><br>
</p>
<p><br>
</p>


</mysql.h></my_global.h>
Copy after login
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

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.

Undress AI Tool

Undress AI Tool

Undress images for free

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)

MySQL's Role: Databases in Web Applications MySQL's Role: Databases in Web Applications Apr 17, 2025 am 12:23 AM

The main role of MySQL in web applications is to store and manage data. 1.MySQL efficiently processes user information, product catalogs, transaction records and other data. 2. Through SQL query, developers can extract information from the database to generate dynamic content. 3.MySQL works based on the client-server model to ensure acceptable query speed.

How to start mysql by docker How to start mysql by docker Apr 15, 2025 pm 12:09 PM

The process of starting MySQL in Docker consists of the following steps: Pull the MySQL image to create and start the container, set the root user password, and map the port verification connection Create the database and the user grants all permissions to the database

Laravel Introduction Example Laravel Introduction Example Apr 18, 2025 pm 12:45 PM

Laravel is a PHP framework for easy building of web applications. It provides a range of powerful features including: Installation: Install the Laravel CLI globally with Composer and create applications in the project directory. Routing: Define the relationship between the URL and the handler in routes/web.php. View: Create a view in resources/views to render the application's interface. Database Integration: Provides out-of-the-box integration with databases such as MySQL and uses migration to create and modify tables. Model and Controller: The model represents the database entity and the controller processes HTTP requests.

Solve database connection problem: a practical case of using minii/db library Solve database connection problem: a practical case of using minii/db library Apr 18, 2025 am 07:09 AM

I encountered a tricky problem when developing a small application: the need to quickly integrate a lightweight database operation library. After trying multiple libraries, I found that they either have too much functionality or are not very compatible. Eventually, I found minii/db, a simplified version based on Yii2 that solved my problem perfectly.

How to install mysql in centos7 How to install mysql in centos7 Apr 14, 2025 pm 08:30 PM

The key to installing MySQL elegantly is to add the official MySQL repository. The specific steps are as follows: Download the MySQL official GPG key to prevent phishing attacks. Add MySQL repository file: rpm -Uvh https://dev.mysql.com/get/mysql80-community-release-el7-3.noarch.rpm Update yum repository cache: yum update installation MySQL: yum install mysql-server startup MySQL service: systemctl start mysqld set up booting

Laravel framework installation method Laravel framework installation method Apr 18, 2025 pm 12:54 PM

Article summary: This article provides detailed step-by-step instructions to guide readers on how to easily install the Laravel framework. Laravel is a powerful PHP framework that speeds up the development process of web applications. This tutorial covers the installation process from system requirements to configuring databases and setting up routing. By following these steps, readers can quickly and efficiently lay a solid foundation for their Laravel project.

MySQL and phpMyAdmin: Core Features and Functions MySQL and phpMyAdmin: Core Features and Functions Apr 22, 2025 am 12:12 AM

MySQL and phpMyAdmin are powerful database management tools. 1) MySQL is used to create databases and tables, and to execute DML and SQL queries. 2) phpMyAdmin provides an intuitive interface for database management, table structure management, data operations and user permission management.

Centos install mysql Centos install mysql Apr 14, 2025 pm 08:09 PM

Installing MySQL on CentOS involves the following steps: Adding the appropriate MySQL yum source. Execute the yum install mysql-server command to install the MySQL server. Use the mysql_secure_installation command to make security settings, such as setting the root user password. Customize the MySQL configuration file as needed. Tune MySQL parameters and optimize databases for performance.

See all articles