Mysql 简明教程

MySQL - Java Syntax

为了与数据库通信，Java 提供了一个称为 JDBC（Java 数据库连接）的库。JDBC 提供了一组专门用于数据库连接的类和方法，使 Java 开发人员能够执行诸如建立连接，执行查询和管理 MySQL 数据库中的数据之类的任务。

To communicate with databases Java provides a library known as JDBC (Java Database Connectivity). JDBC provides a set of classes and methods specifically designed for database connectivity, enabling Java developers to perform tasks such as establishing connections, executing queries, and managing data in MySQL databases.

JDBC Installation

若要将 MySQL 与 Java 一起使用，您需要使用 JDBC（Java 数据库连接）驱动程序将 Java 应用程序连接到 MySQL 数据库。以下是安装和使用 MySQL Connector/J（Java 的官方 MySQL JDBC 驱动程序）的常规步骤 −

To use MySQL with Java, you need to use a JDBC (Java Database Connectivity) driver to connect your Java application to a MySQL database. Below are the general steps for installing and using the MySQL Connector/J, which is the official MySQL JDBC driver for Java −

Step 1: Download MySQL Connector/J

访问官方 MySQL Connector/J 下载页面：MySQL Connector/J Downloads。

Visit the official MySQL Connector/J download page: MySQL Connector/J Downloads.

Step 2: Select the Appropriate Version

根据您的 MySQL 服务器版本和 Java 版本选择合适版本。下载包含 JDBC 驱动程序的 ZIP 或 TAR 归档文件。

Choose the appropriate version based on your MySQL server version and Java version. Download the ZIP or TAR archive containing the JDBC driver.

Step 3: Extract the Archive*

将已下载存档的内容提取到您电脑上的某一位置。

Extract the contents of the downloaded archive to a location on your computer.

Step 4: Add Connector/J to Your Java Project*

在您的 Java 项目中，将 Connector/J JAR 文件添加到您的类路径。您能在您的 IDE 中执行此操作，或通过将 JAR 文件手动复制到您的项目中。

In your Java project, add the Connector/J JAR file to your classpath. You can do this in your IDE or by manually copying the JAR file into your project.

Step 5: Connect to MySQL Database in Java*

在您的 Java 代码中，使用 JDBC API 连接到 MySQL 数据库。

In your Java code, use the JDBC API to connect to the MySQL database.

Java Functions to Access MySQL

以下是访问 Java 中 MySQL 的主要函数 -

Following are the major functions involved in accessing MySQL from Java −

Basic Example

若要使用 Java 连接到 MySQL 数据库并与其通信，您可以按照以下步骤操作 -

To connect and communicate with a MySQL database using Java, you can follow these steps −

Load the JDBC driver specific to your database.
Create a connection to the database using "DriverManager.getConnection()".
Create a "Statement" or "PreparedStatement" for executing SQL queries.
Use "executeQuery()" for SELECT queries, or "executeUpdate()" for other statements.
Iterate through the "ResultSet" to process the retrieved data.
Close "ResultSet", "Statement", and "Connection" to release resources.
Wrap database code in try-catch blocks to handle exceptions.
Use transactions if performing multiple operations as a single unit.

以下示例显示了 Java 程序调用任何 MySQL 查询的通用语法 -

The following example shows a generic syntax of a Java program to call any MySQL query −

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class DatabaseInteractionExample {

    public static void main(String[] args) {
        try {
            // Load JDBC Driver
            Class.forName("com.mysql.cj.jdbc.Driver");

            // Connect to Database
            Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/your_database", "your_username", "your_password");

            // Execute Query
            Statement statement = connection.createStatement();
            ResultSet resultSet = statement.executeQuery("Your SQL Query");

            // Process Results
            while (resultSet.next()) {
                // Process data
            }

            // Close Resources
            resultSet.close();
            statement.close();
            connection.close();

            // Handle Exceptions
        } catch (ClassNotFoundException | SQLException e) {
            e.printStackTrace();
        }
    }
}