Question

有没有办法改进这个查询，我对返回的结果非常满意，但性能非常差，在这种情况下联合会导致往返吗？通过使用存储过程获得性能，这样的事情是否可能？是否有可能在结果上进行自我加入，这会提高性能吗？

        List<string> words = Util.Search.SplitByWhiteSpace(q);

        using (WebsitesDataContext context = new WebsitesDataContext())
        {
            IQueryable<WebsitesRanked> query = Enumerable.Empty<WebsitesRanked>().AsQueryable();
            query = query.Union(context.Websites.Where(x => x.Title.Contains(q)).Select(x => new WebsitesRanked { Webiste = x, Rank = 100 }));
            query = query.Union(context.Websites.Where(x => x.Description.Contains(q)).Select(x => new WebsitesRanked { Webiste = x, Rank = 100 }));
            query = query.Union(context.Websites.Where(x => x.Keywords.Contains(q)).Select(x => new WebsitesRanked { Webiste = x, Rank = 100 }));
            query = query.Union(context.Websites.Where(x => x.Url.Contains(q)).Select(x => new WebsitesRanked { Webiste = x, Rank = 100 }));

            foreach (var word in words)
            {
                string keyword = word;
                query = query.Union(context.Websites.Where(x => x.Title.Contains(word)).Select(x => new WebsitesRanked { Webiste = x, Rank = 20 }));
                query = query.Union(context.Websites.Where(x => x.Description.Contains(word)).Select(x => new WebsitesRanked { Webiste = x, Rank = 20 }));
                query = query.Union(context.Websites.Where(x => x.Keywords.Contains(word)).Select(x => new WebsitesRanked { Webiste = x, Rank = 20 }));
                query = query.Union(context.Websites.Where(x => x.Url.Contains(word)).Select(x => new WebsitesRanked { Webiste = x, Rank = 20 }));
            }

           var results = query.GroupBy(x => x.Webiste).Select(x => new WebsitesRanked { Webiste = x.First().Webiste, Rank =  x.Sum(s => s.Rank) }).OrderByDescending(x => x.Rank).Select(x => x.Webiste);
        }

Answer 1

你可以创建字典表：一个表分区的字母（表格分区为单词，以'a'开头，另一个'b'......）此表将包含以下列：

column 1:Word (each word in your table will be setted here using a nightly schedule task or Background schedule task)
column 2:Website 
column 3:Rank (each time a word is found, increment this rank)

只有一个表可以查询并使用分区执行，您将获得良好的性能，因为工作将在计划任务中完成

提高网站数据库的搜索性能

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