java - 如何使用Java插入mysql数据库(how to insert into mysql database with java)

Question

i want to insert inputs i take from user into mysql database the connection is right but the insertion gives me error

(我想将我从用户那里获取的输入插入到mysql数据库中，连接正确，但是插入却给我错误)

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax;

(com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException：SQL语法有错误；)

check the manual that corresponds to your MariaDB server version for the right syntax to use near ''u_fname', 'u_lname', 'u_uname', 'u_pass', 'u_age', 'u_adderess') values('20','o' at line 1

(检查与您的MariaDB服务器版本相对应的手册以获取正确的语法，以在``u_fname''，``u_lname''，``u_uname''，``u_pass''，``u_age''，``u_adderess''）值（'20'，'o '在第1行)

My code is:

(我的代码是：)

public void adduser(User s) {
   try {
        sql = "insert into users ('u_fname', 'u_lname', 'u_uname', 'u_pass', 'u_age', 'u_adderess')"
                + "values('" + s.getFirstname() + "','" + s.getLastname()
                + "','" + s.getUsername() + "','" + s.getPassword() + "','" + s.getAge() + "','" + s.getAdderss() + "')";
        stmt = conn.createStatement();
        int i = stmt.executeUpdate(sql);
        if (i > 0) {
            System.out.println("ROW INSERTED");
        } else {
            System.out.println("ROW NOT INSERTED");
        }
    } catch (Exception e) {
        System.out.println(e);
    }

}

  ask by Omar Mohamed translate from so

Answer 1

To insert into mysql, follow these steps-

(要插入mysql，请按照以下步骤操作：)

1. Create a Java Connection to our example MySQL database.

   (创建一个到我们的示例MySQL数据库的Java连接。)

   I believe you already took care of it.

   (我相信您已经照顾好了。)

   It will be something like this-

   (这将是这样的-)

     String myDriver = "org.gjt.mm.mysql.Driver"; String myUrl = "jdbc:mysql://localhost/test"; Class.forName(myDriver); Connection conn = DriverManager.getConnection(myUrl, "root", ""); 

2. Create a SQL INSERT statement, using the Java PreparedStatement syntax.

   (使用Java PreparedStatement语法创建SQL INSERT语句。)

   Your PreparedStatement SQL statement will be as following this format-

   (您的PreparedStatement SQL语句将采用以下格式-)
   

     String sql = " insert into users (first_name, last_name, date_created, is_admin, num_points)" + " values (?, ?, ?, ?, ?)"; 

3. Set the fields on our Java PreparedStatement object.

   (在我们的Java PreparedStatement对象上设置字段。)

   It will done as-

   (它将作为)
   

     PreparedStatement preparedStmt = conn.prepareStatement(sql); preparedStmt.setString (1, s.first_name); preparedStmt.setString (2, s.last_name); preparedStmt.setDate (3, s.date_created); preparedStmt.setBoolean(4, s.is_admin); preparedStmt.setInt (5, s.num_points); 

4. Execute a Java PreparedStatement.

   (执行Java PreparedStatement。)

     preparedStmt.execute(); 

5. Close our Java MYSQL database connection.

   (关闭我们的Java MYSQL数据库连接。)

     conn.close(); 

6. Catch any SQL exceptions that may come up during the process.

   (捕获过程中可能出现的所有SQL异常。)

     catch (Exception e) { System.err.println("Got an exception!"); // printStackTrace method // prints line numbers + call stack e.printStackTrace(); // Prints what exception has been thrown System.out.println(e); }