sql - 从存储过程中的表中返回所有 ID

Question

我继续探索 SQL 和存储过程，但遇到了 @feedid 仅返回 1 个 ID 的问题，但它有 for ex。 20.如何返回id数组？

CREATE PROC spGetItemsByUser
    @userName NVARCHAR(50)
AS BEGIN

    DECLARE @userId INT,
            @feedId INT;

    SELECT @userId = ID
    FROM users
    WHERE name = @userName

    SELECT @feedId = feedid
    FROM userstofeed
    WHERE userid = @userId

    SELECT *
    FROM feed
    WHERE ID = @feedId

END

Answer 1

你必须使用表变量:

declare @userId table (uid int)
declare @feedId table (id int)

insert into @userid(uid)
select id 
from Users 
where name = @userName

insert into @feedid(id)
select feedid 
from userstofeed 
where userid in (select uid from @userId)

select * from feed where id in (select id from @feedId)