查询中的订单条款 [英] ORDER CLAUSE IN QUERY

问题描述

亲爱的所有人，
我在Windows窗体中必须自动生成唯一的Job代码.
我选择了从数据库添加的最后一行，并用一个递增jobpk(自动生成主键)，并使用字符串代码进行连接.

我有以下代码，但是查询在
返回异常

 dAdapter.Fill(ds，" );  

 ORDER BY子句中的语法错误.
 

我的代码是:

 公共  void  newjobecodenoget(){
           OleDbConnection oleDbConnection1 = 新 System.Data.OleDb.OleDbConnection(connString);
           oleDbConnection1.Open();


           字符串查询= " ;
           OleDbDataAdapter dAdapter = 新 OleDbDataAdapter(query，connString);


           DataSet ds = 新 DataSet();

           dAdapter.Fill(ds，" )；
            Int32  S =  int  .Parse(ds.Tables [ 0 ].Rows [ 0 ] [ 0 ].ToString());
           S ++;
            MessageBox.Show("  + S);
            字符串 jobcodeno = "  + S .ToString();
            txtjobcode.Text = jobcodeno.ToString();

       }
 

我在构造函数中调用此函数，并且正在使用Access数据库.

jobpk是长整数格式的主键.



谁能帮我解决我的错误?



我尝试在查询中对jobpk使用引号('''')，但结果相同
解决方案
 
如果我没记错的话，Access不知道LIMIT关键字. 



而不是使用
 选择 jobpk  from  jobcodemastertable  BY  jobpk  1  
 

尝试使用
  SELECT   TOP   1  jobpk  FROM  jobcodemastertable  ORDER   BY  jobpk  DESC  
 

 
 
尝试此
 "  
 



 我不确定我是否尝试在sqlserver 2005中使用，但

 "  
 

 不起作用，但我可以使用

 "  
 
 
 
请尝试以下查询



字符串查询= "  
 



或



字符串查询= "  
 
 
 
Dear all,

I am doing a Windows Form where I had to auto generate a Job code which is unique.

This I had done by selecting the last row added from the database and incrementing jobpk(auto generating primary key) with one and concatenating with a string code.



I had code as below, but the query returns an exception at

dAdapter.Fill(ds, "tbljobrdataview");


Syntax error in ORDER BY clause.


My code is:

public void newjobecodenoget(){
           OleDbConnection oleDbConnection1 = new System.Data.OleDb.OleDbConnection(connString);
           oleDbConnection1.Open();


           String query = "Select jobpk from jobcodemastertable ORDER BY jobpk DESC LIMIT 1";
           OleDbDataAdapter dAdapter = new OleDbDataAdapter(query, connString);


           DataSet ds = new DataSet();

           dAdapter.Fill(ds, "tbljobrdataview");
           Int32  S = int.Parse(ds.Tables[0].Rows[0][0].ToString());
           S++;
            MessageBox.Show("" +S);
            String jobcodeno = "NFT" + S.ToString();
            txtjobcode.Text = jobcodeno.ToString();

       }


I call this function at constructor and I am using Access database.

jobpk is primary key in long integer format.



Can anyone help to sort out my mistake?



I have tried using quotes('''') to jobpk in query but same result
解决方案
If I am not mistaken Access does not know the LIMIT keyword.



Instead of using 
Select jobpk from jobcodemastertable ORDER BY jobpk DESC LIMIT 1


try using 
SELECT TOP 1 jobpk FROM jobcodemastertable ORDER BY jobpk DESC


instead.

Try this 
"Select Top(1) jobpk from jobcodemastertable ORDER BY jobpk DESC"




 i''m not sure i try in sqlserver 2005 but 

"Select jobpk from jobcodemastertable ORDER BY jobpk DESC LIMIT 1"


 not work but i can use 

"Select Top(1) jobpk from jobcodemastertable ORDER BY jobpk DESC"

Hi, try below query



String query = "Select Max(jobpk) from jobcodemastertable"




or



String query = "Select top 1 jobpk from jobcodemastertable order by jobpk DESC"


                        
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