首页 \ 问答 \ 为什么mongoDB使用objectID？(Why mongoDB uses objectID?)

为什么mongoDB使用objectID？(Why mongoDB uses objectID?)

{ "_id" : ObjectId("4c2209f9f3924d31102bd84a"), "name" : "mongo" }
 
 objectId究竟是什么目的？ 这是使用时间戳生成的大数字。  
 如果我看到任何nosql是键值，我用键查询值。  
 这里我们使用key和value作为数据并使用find（）函数。  
 那么，我想知道什么时候我们真的需要objectid？ 授予用户访问权限以查看对象ID值的原因是什么？  
 阅读文档后，一个基本问题是mongo DB作为哈希表类型实现？ 

{ "_id" : ObjectId("4c2209f9f3924d31102bd84a"), "name" : "mongo" }
 
what exactly is the purpose of objectId? It's a big number that is generated using a timestamp. 
If I see any nosql which is key-value, I query with key the value. 
Here we use key and value in the as the data and use find () function. 
So, I am trying to understand when we really need the objectid? What are the reasons behind that giving access to the user to view the value of the object ID? 
After reading the docs, one basic question is mongo DB as hash table type implementation?

原文：https://stackoverflow.com/questions/6560928

更新时间：2022-07-05 07:07

最满意答案

 我用了  
  type: "GET",
  url: "http://stackoverflow.com/questions/32554239/ajax-post-without-refresh", 
 
 而不是你的  
   type: "POST",
  url: "http://****/new/action.php",  
 
 它工作正常。 （只需点击“运行代码段”，它会显示错误，因为该网址不支持跨域）  
 
  
  $(document).ready(function() {  
  $("form#iscrizione").submit(function(){   
    var ordine = $("#ordine").val();  
    var cognome = $("#cognome").val();
    $.ajax({  
      type: "GET",
      url: "http://stackoverflow.com/questions/32554239/ajax-post-without-refresh",  
      data: "cognome=" + cognome + "&ordine=" + ordine,
      dataType: "html",
      success: function(risposta) {  
        $("div#risposta").html(risposta);  
        alert("ok!");
      },
      error: function(){
              alert("Chiamata fallita!!!");
}
    }); 
    return false;  
  });
}); 
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<form id="iscrizione"> 
  
  <input type="text" value="get" id="cognome"><input type="text" value="get" id="ordine"><input type="submit" value="get"></form><div id="risposta"></div> 
  
 

I used  
  type: "GET",
  url: "http://stackoverflow.com/questions/32554239/ajax-post-without-refresh", 
 
instead of your  
   type: "POST",
  url: "http://****/new/action.php",  
 
AND it works fine. (Just click on "Run snippet", it shows an error because the url doesn't support cross-domain)  
 
  
  $(document).ready(function() {  
  $("form#iscrizione").submit(function(){   
    var ordine = $("#ordine").val();  
    var cognome = $("#cognome").val();
    $.ajax({  
      type: "GET",
      url: "http://stackoverflow.com/questions/32554239/ajax-post-without-refresh",  
      data: "cognome=" + cognome + "&ordine=" + ordine,
      dataType: "html",
      success: function(risposta) {  
        $("div#risposta").html(risposta);  
        alert("ok!");
      },
      error: function(){
              alert("Chiamata fallita!!!");
}
    }); 
    return false;  
  });
}); 
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<form id="iscrizione"> 
  
  <input type="text" value="get" id="cognome"><input type="text" value="get" id="ordine"><input type="submit" value="get"></form><div id="risposta"></div>

为什么mongoDB使用objectID？(Why mongoDB uses objectID?)

最满意答案

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