c# - IndexOutOfRangeException SqlDataReader 从表中读取 bool 值

Question

我有 3 个表:users、feed(id,body,title,link) 和 userstofeed(id,userid,feedid,isread) 当我试图从 userstofeed 表中读取 bool 值时它带来了 IndexOutOfRangeException。请告诉我我做错了什么

while (reader.Read())
{
     rssFeed.Title = reader["title"].ToString();
     rssFeed.Body = reader["body"].ToString();
     rssFeed.Link = reader["link"].ToString();
     rssFeed.IsRead = (bool) reader["isread"]; //IndexOutOfRangeException here
     yield return rssFeed;
}

这里是sql存储过程:

create proc spGetItemsByUser
@userName nvarchar(50)
as
begin
declare @userId int
declare @feedId table (id int)

select @userId = id 
from Users 
where name = @userName

insert into @feedid (id)
select feedid, isread 
from userstofeed 
where userid = @userId

select * from feed where id in (select id from @feedId)
select isread from userstofeed where userid = @userId //Here I'm getting bit if it read or not
end

Answer 1

将存储过程中的 SELECT 更改为:

SELECT [feed].[title], [feed].[body], [feed].[link], [userstofeed].[isread]
FROM [feed]
INNER JOIN [userstofeed] ON ([userstofeed].userid = @userId)
WHERE [feed].[id] in (select id from @feedId)

我认为在您的版本中 isread 不是第一个结果集的列。 isread 值作为行附加在 title、feed 和 body 的行之后。

---

正如 Zohar Peled 所建议的，我尝试对整个存储过程进行重构:

CREATE PROC spGetItemsByUser
   @userName nvarchar(50)
AS
BEGIN
    SELECT [feed].[title], [feed].[body], [feed].[link], [userstofeed].[isread]
    FROM [feed]
    INNER JOIN [userstofeed] ON ([userstofeed].[feedid] = [feed].[id])
    INNER JOIN [users] ON ([users].[id] = [userstofeed].[userid])
    WHERE [users].[name] = @userName
END