linq - 在 linq 查询中有条件 count()

Question

我想创建这个查询:

select Something, count(Something) as "Num_Of_Times"
from tbl_results
group by Something
having count(Something)>5

我从这个开始:

tempResults.GroupBy(dataRow => dataRow.Field<string>("Something"))
   .Count() //(.......what comes here , to make Count()>5?)

Answer 1

from item in tbl_results
group item by item.Something into groupedItems
let count = groupedItems.Count()
where count > 5
select new { Something = groupedItems.Key, Num_Of_Times = count };

更新:这会给你的结果为 IQueryable<DataRow> :

DataTable dt= new DataTable();
dt.Columns.Add("Something", typeof(int));
dt.Columns.Add("Num_Of_Times", typeof(int));

var results =   (from item in tbl_results
                 group item by item.Something into groupedItems
                 let count = groupedItems.Count()
                 where count > 2
                 select dt.Rows.Add(groupedItems.Key, count)).AsQueryable();

(请注意，它还填充了 dt 表)