Java Mysql 简明教程

Java & MySQL - Drop Table Example

本章提供了一个有关如何使用 JDBC 应用程序删除表的示例。在执行以下示例之前,请确保以下内容就绪:

This chapter provides an example on how to delete a table using JDBC application. Before executing the following example, make sure you have the following in place −

  1. To execute the following example you can replace the username and password with your actual user name and password.

  2. Your MySQL database you are using, is up and running.

NOTE -这是一项严肃的操作,在继续删除表之前您必须做出坚定的决定,因为表中的所有内容都将丢失。

NOTE − This is a serious operation and you have to make a firm decision before proceeding to delete a table, because everything you have in your table would be lost.

Required Steps

创建新的数据库使用 JDBC 应用程序需要执行以下步骤:

The following steps are required to create a new Database using JDBC application −

  1. Import the packages − Requires that you include the packages containing the JDBC classes needed for database programming. Most often, using import java.sql.* will suffice.

  2. Open a connection − Requires using the DriverManager.getConnection() method to create a Connection object, which represents a physical connection with a database server.

  3. Execute a query − Requires using an object of type Statement for building and submitting an SQL statement to drop a table in a seleted database.

  4. Clean up the environment − try with resources automatically closes the resources.

Sample Code

将以下示例复制并粘贴到 TestApplication.java 中,如下进行编译和运行:

Copy and paste the following example in TestApplication.java, compile and run as follows −

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

public class TestApplication {
   static final String DB_URL = "jdbc:mysql://localhost/TUTORIALSPOINT";
   static final String USER = "guest";
   static final String PASS = "guest123";

   public static void main(String[] args) {
      // Open a connection
      try(Connection conn = DriverManager.getConnection(DB_URL, USER, PASS);
         Statement stmt = conn.createStatement();
      ) {
         String sql = "DROP TABLE REGISTRATION";
         stmt.executeUpdate(sql);
         System.out.println("Table deleted in given database...");
      } catch (SQLException e) {
         e.printStackTrace();
      }
   }
}

现在让我们如下编译上述示例:

Now let us compile the above example as follows −

C:\>javac TestApplication.java
C:\>

运行 TestApplication 时,它会生成以下结果:

When you run TestApplication, it produces the following result −

C:\>java TestApplication
Table deleted in given database...
C:\>