使用LINQ 2 SQL从数据库表中检索随机记录/行? [英] Retrive Random Record/Row from DataBase Table Using LINQ 2 SQL?

问题描述

我在Default.aspx页上有一个每日报价标签".我的要求是我希望从数据库表报价"中选择一个随机报价，并将文本分配给报价标签"，我正在使用Linq 2 SQL ??

这是我的GetAll()Linq 2 Sql查询

I have a "Quote of the Day Label" on my Default.aspx Page My requirement is that I want a random quote to be selected from the database table "Quotes" and assign the text to the "Quotelabel", I am Using Linq 2 Sql??

here''s my GetAll() Linq 2 Sql query

public static List<Quotes> GetAll()
{
    List<Quotes> list = new List<Quotes>();
    var query = from c in new HsInternetDBDataContext().Quotes
                orderby c.DateCreated ascending
                select c;
    foreach (DAL.Quote dr in query.ToList())
    {
        l.Add(new Quotes(dr));
    }
    return list;
}

如何修改上述查询并从数据库中获得一个随机记录/报价?
或使用此GetAll()方法并在客户端选择一个随机记录以分配给我的QuoteLabel?

谢谢
Chetan.

how do i modify the above query and get a single Random record/Quote from database??
or use this GetAll() method and select a single random record on the client side to assign to my QuoteLabel??

Thank you,
Chetan.

推荐答案

读取所有引号并删除除一个引号外的所有引号似乎是浪费的.我将使用Linq2Sql功能来检索单个项目，如下所示:

首先，我将使用Count()查询报价数量.然后，我将生成一个介于0和Count()-1(含)之间的随机整数R.最后，我将使用Link2Sql来获得第R个报价，例如:

Reading all quotes and dropping all but one seems wasteful. I would use Linq2Sql capabilities to retrieve a single item, like this:

First, I would query the number of quotes using Count(). Then, I would generate a random integer R between 0 and Count()-1, inclusive. Finally, I would use Link2Sql to get R-th quote, like this:

var quote = new HsInternetDBDataContext()
    .Quotes
    .OrderBy(q => q.DateCreated)
    .Skip(R)
    .Take(1)
    .Single();

祝你好运！

Good luck!

http://www.dailycoding.com/Posts/random_sort_a_list_using_linq. aspx [ ^ ]解释了如何随机排序一个列表.完成后，您可以选择最高值.

http://www.dailycoding.com/Posts/random_sort_a_list_using_linq.aspx[^] explains how to random sort a list. Once you do that, you can select the top value.

谢谢大家，让它在我的解决方案中起作用:

Thanks guys, got it working here''s my solution:

public static Quotes GetRandomQuotes()
{
    HsInternetDBDataContext db = new HsInternetDBDataContext();
    
    var query = from c in db.Quotes select c;
    int count = query.Count();
    if (query.Count() > 0)
    {
        Random r = new Random();
        return new Quotes(query.ToList()[r.Next(0, count)]);
    }
    else
    {
        return new Quotes();
    }
}

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