Question

我有一个新的疑问。我想在macfast数据库中创建一个名为admin的表。该表创建成功，但是当我以手动方式插入值（使用查询）时，它似乎是一个错误。我的代码如下

  public void createTableAdmin() {
    try{

            Class.forName("com.mysql.jdbc.Driver");
            conn = (Connection) DriverManager.getConnection(DB_URL_table, USER, PASS);
            stmt = (Statement) conn.createStatement();

            String sql1 = "CREATE TABLE IF NOT EXISTS admin " +
                    "(id INTEGER not NULL, " +
                    " user_name VARCHAR(255), " + 
                    " password VARCHAR(255), " + 
                    " isAdmin BOOLEAN NOT NULL DEFAULT '0', " +  
                    " PRIMARY KEY ( id ))"; 
            stmt.executeUpdate(sql1);

            String insert="INSERT INTO admin(id,user_name,password,isAdmin)VALUES(1,admin,admin,1)";
            stmt.executeUpdate(insert);


        }catch(SQLException se){
                //Handle errors for JDBC
                se.printStackTrace();
        }catch(Exception e){
                //Handle errors for Class.forName
                e.printStackTrace();
        }finally{
                //finally block used to close resources
        try{
                if(stmt!=null)
                conn.close();
        }catch(SQLException se){
        }// do nothing
        try{
                if(conn!=null)
                conn.close();
        }catch(SQLException se){
                se.printStackTrace();
        }//end finally try
  }//end try

 }

错误类似于

 com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column 'admin' in 'field list'
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

Answer 1

''列值附近缺少引号VARCHAR。

String insert = "INSERT INTO admin (id,user_name,password,isAdmin) " +
                "VALUES (1, 'admin', 'admin', 1)";

Answer 2

您没有正确引用字符串;

String insert=
   "INSERT INTO admin(id,user_name,password,isAdmin)VALUES(1,admin,admin,1)";

应该是

String insert=
   "INSERT INTO admin(id,user_name,password,isAdmin)VALUES(1,'admin','admin',1)";

Answer 3

您的值需要引号，或者它们被视为字段名称。

public void createTableAdmin（）{ 尝试{

        Class.forName("com.mysql.jdbc.Driver");
        conn = (Connection) DriverManager.getConnection(DB_URL_table, USER, PASS);
        stmt = (Statement) conn.createStatement();

        String sql1 = "CREATE TABLE IF NOT EXISTS admin " +
                "(id INTEGER not NULL, " +
                " user_name VARCHAR(255), " + 
                " password VARCHAR(255), " + 
                " isAdmin BOOLEAN NOT NULL DEFAULT '0', " +  
                " PRIMARY KEY ( id ))"; 
        stmt.executeUpdate(sql1);

        String insert="INSERT INTO admin(id,user_name,password,isAdmin)VALUES(1,'admin','admin',1)";
        stmt.executeUpdate(insert);


    }catch(SQLException se){
            //Handle errors for JDBC
            se.printStackTrace();
    }catch(Exception e){
            //Handle errors for Class.forName
            e.printStackTrace();
    }finally{
            //finally block used to close resources
    try{
            if(stmt!=null)
            conn.close();
    }catch(SQLException se){
    }// do nothing
    try{
            if(conn!=null)
            conn.close();
    }catch(SQLException se){
            se.printStackTrace();
    }//end finally try

} //结束尝试

}

价值插入错误

3 个答案: