ASP.Net MVC 6线程优化

如何解决ASP.Net MVC 6线程优化

寻找有关使用Thread的建议。

我有控制器，该控制器在DB中进行查询并转换List中的选定数据。但是在某些情况下，我需要几行的额外信息。我不想为每行循环查询。 如果我要启动新线程，它将与我的主循环并行进行额外的查询，并将额外的信息添加到列表中。好还是不好。或者最好先获取所有数据。

示例：

    [HttpPost]
      public async Task<IActionResult> ReestrRazr(DateTime date)
      {
        List<SomeClass> arr = new List<SomeClass>();
 string query = " SELECT [table].[id],[table].[snumber],[table].[datein],[table].[datefileeate],[table].[istatusU],[table].[datezamechania],[table].[type],[table].[isubtypeU],";
                query += " [tableT3040].[content] as [address],[tableT3040].[nazvanie] as [objNazvanie],";
                query += " [tableT101].[nazvanie] as zastrName,";
                query += " [adress].[rajon],";
                query += " [objT3].[idcomlinknypredstavitelpurpose] as [nadzor] ";

                query += " FROM ((((((((([table] ";
                query += "  JOIN [link] on (([table].[id]=[link].[idlinkper]) and ([link].[ideletestate]=0)) ) ";
                query += " JOIN [file] on (([file].[id]=[link].[idlink]) and ([file].[sfileextension] like ('%pdf%')) and ([file].[ideletestate]=0)) ) ";
                query += " JOIN [obj] ON ([table].[identity]=[obj].[id] AND [obj].[ideletestate]=0)  ) ";
                query += " LEFT JOIN [objT] as [objT3] on (([objT3].[identity]=[obj].[id]) and ([objT3].[type]=3) and ([objT3].[ideletestate]=0)) )";
                query += " LEFT JOIN [adress]  ON (([obj].[idaddress]=[adress].[id]) and ([adress].[ideletestate]=0) and ([adress].[workstate]=1)) ) ";
                query += " LEFT JOIN [objT] as [objT119] on (([objT119].[identity]=[obj].[id]) and ([objT119].[type]=119) and ([objT119].[ideletestate]=0) and ([objT119].[idcomlinknypredstavitelpurpose] = 1)) )";
                query += " LEFT JOIN [tableT] as [tableT3040] on (([table].[id]=[tableT3040].[idlinkper]) and ([tableT3040].[type]=3040) and ([tableT3040].[ideletestate]=0)) ) ";
                query += " LEFT JOIN [tableT] as [tableT101] on (([table].[id]=[tableT101].[idlinkper]) and ([tableT101].[type]=101) and ([tableT101].[nazvanie] <> '') and ([tableT101].[nazvanie] is not null) and ([tableT101].[ideletestate]=0)) )";
                query += " left join [ae] on (([table].[idcomlinkny]=[ae].[id]) and ([ae].[ideletestate]=0)) ) ";
        DataTable dt = Execute4Table(query + $" where date >'{date.tostring("yyyyMMdd")}'")
        foreach (DataRow row in dt.Rows)
        {
          int id = Convert.ToInteger(row[0]);
          int type = Convert.ToInteger(row[1]);
          string number= Convert.ToString(row[2]);
         
          SomeClass sc = new SomeClass();
          sc.id=id;
          sc.number = number;
    
          if (type==50)
           {
            number = Convert.ToString(ExecuteScalar("select number from table WHERE idparent="+ id.tostring()));
           }
    
          arr.Add(sc);
        }
    }

谢谢！（对不起我的英语） 附言实际查询有8个JOIN，获得所有必要的信息将导致JOIN的数量增加到12-13。这对性能不利。

解决方法

您将无法从同一DbContext（请求范围）运行并行查询。我可以对一个查询执行left outer join，它将为您带来所需的所有数据，其他行为null，或者允许客户端对这些行（请求/行）提出额外的请求。尽管我会坚持第一个想法，但前提是不会发现那些“额外”会导致查询的基本版本大大降低速度。 3ed选项是仅对主查询使用await，从内存结果中收集选定的ID，然后对IN进行第二次查询，以稍后在内存中分配值。