Question

我正在尝试创建一个程序，从用户那里获取输入并使用输入作为数据库名创建一个mysql数据库，我成功创建了数据库，但只有当我自己在代码中输入数据库名称时，我才会想到到目前为止

package mqsljava;

import java.sql.Connection;
import java.sql.Statement;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Scanner;
public class Mqsljava {

//CONNECTION

public static Connection getConnection() throws Exception {
    String driver = "com.mysql.jdbc.Driver";
    String url = "jdbc:mysql://localhost:3306/";
    String username = "root";
    String password = "";
    Class.forName(driver);
    Connection conn = DriverManager.getConnection(url, username, password);
    return conn;
  }


  public static void main(String[] args) {
     //THE VARIABLE TO STORE USER INPUT
        String Data;
     //SCANNER TO GET USER INPUT
        Scanner Dbname = new Scanner(System.in);
    System.out.println("Enter your db name");
    //VARIABLE SAVES USER INPUT
    Data = Dbname.nextLine();

    //WHERE THE PROBLEM IS, USING USER INPUT DATA TO CREATE DATABASE

    String EMPLOYEE_DB = " CREATE DATABASE '"+Data+"' ";
        Connection conn = null;
    Statement stmt = null;
    try {
      conn = getConnection();
      stmt = conn.createStatement();
      stmt.executeUpdate(EMPLOYEE_DB);
      System.out.println("Database created.");

    } catch (ClassNotFoundException e) {
      System.out.println("error: failed to load MySQL driver.");
      e.printStackTrace();
    } catch (SQLException e) {
      System.out.println("error: failed to create a connection object.");
      e.printStackTrace();
    } catch (Exception e) {
      System.out.println("other error:");
      e.printStackTrace();
    } finally {
      try {
        stmt.close();
        conn.close();        
      } catch (SQLException e) {
        e.printStackTrace();
      }
    }
    }

    }

但我一直收到错误

com.mysql.jdbc.exceptions.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''Data'' at line 1
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:936)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2985)
    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1631)
    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1723)
    at com.mysql.jdbc.Connection.execSQL(Connection.java:3277)
    at com.mysql.jdbc.Statement.executeUpdate(Statement.java:1402)
    at com.mysql.jdbc.Statement.executeUpdate(Statement.java:1317)
    at mqsljava.Mqsljava.main(Mqsljava.java:52)

我认为我没有使用正确的陈述，我尝试了很多东西，但仍然无法正常工作

Answer 1

要创建数据库，您不需要使用Supplier，您必须使用不带'DB_NAME'的名称，如下所示：

''

与@baao在评论中提及一样，您的方式不安全且对SQL注入开放，您必须在查询中使用它之前检查名称。

获取用户输入以创建mysql数据库

1 个答案: