Javscript - 如何在不使用自动增量的情况下增加sql表中的数字 [英] Javscript-How to increment a number in an sql table without using autoincrement

问题描述

例如：cust_code = 000001，这应该是我的customer表中的起始cust_code，并且应该像000002,000003..etc那样相应地增加...将新字段插入到此表中，这意味着按表应该看起来像， />
cust_code cust_name

000001 abc

000002 dca

。

。

。然后继续。

For example: cust_code=000001,this should be the starting cust_code in my customer table and should increment accordingly like 000002,000003..etc.. on inserting new fields into this table that means by table should look like,
cust_code cust_name
000001 abc
000002 dca
.
.
.and it goes on.

function pad(number, length)
{
   alert(number);
    var str = '' + number;
    while (str.length < length)
     {
        str = '0' + str;
    }

      return '000'+str;

}

var s="000001";

var number=parseInt(s.substring(3,6),10)+1;
         var value=pad(number,3);

		      transaction.executeSql('INSERT INTO customer(cust_code,cust_name)VALUES(?,?)',[value,$('#name').val()],populate_success,transaction_error );

我试过这段代码，但每次都是我插入，cust_code将与000002相同，因为我给出的初始值是000001.

任何人都可以帮我解决这个问题......

I have tried this code but everytime I insert, the cust_code will be same as 000002,because the initial value I have given is 000001.
Can anybody help me to solve this...

推荐答案

（' ＃name'）。val（）]，populate_success，transaction_error） ;

('#name').val()],populate_success,transaction_error );

我尝试过这段代码，但每次插入时，cust_code都与000002相同，因为我给出的初始值是000001.

任何人都可以帮我解决这个问题......

I have tried this code but everytime I insert, the cust_code will be same as 000002,because the initial value I have given is 000001.
Can anybody help me to solve this...

不要。甚至不要考虑它。



停下片刻，想想你想要做什么：这是一个网站，意味着多个同步更新。在网上，这是缓慢的，非确定性的。通过Web服务器（或者更可能是Web服务器场，这意味着每次用户与之通信时，您可能无法获得相同的物理服务器）。这将与运行SQL的不同计算机（或很可能是SQL服务器场中的许多此类服务器之一）进行通信，因此，您可能不会连续两次获得同一台计算机。



你将要让浏览器说：给我使用最多的号码，增加它，然后将它作为它的号码保存回数据库？



你真的意识到灾难和不可预测的错误的秘诀是什么，不是吗？



Auto增量字段有一个原因：使用它们。以免SQL解决问题并返回给你刚才分配的数字。

Don't. Don't even think about it.

Stop for a moment and think about what you are trying to do: This is a website, which implies multiple simultaneous updates. Over the net, which is slow, and non-deterministic. via a webserver (or more likely a web server farm, which means you probably won't get the same physical server each time the user communicates with it). Which will talk to a different computer running SQL (or quite likely, one of a number of such servers in an SQL server farm, so again, you probably won't get the same computer twice in a row).

And you are going to have the browser say: "Give me the highest number in use", increment it, and then save it back to the database as "it's" number?

You do realize what a recipe for disaster and unpredictable bugs that is, don't you?

Auto increment fields are there for a reason: use them. Lest SQL sort out teh problems and return to you the number it just assigned.

首先你的s是本地的，每次尝试更新时都会启动。将其声明为全局并仅初始化一次并继续更新。对于填充，请按照链接 [ ^ ]

First of all your s is local and being initiated every time you try to update. Declare it as global and initialize it just once and continue updating. And for padding follow the link[^]

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