if object_id('[memberdetails]') is not null drop table [memberdetails]
go
create table [memberdetails]([memberid] int,[firstname] varchar(2),[lastname] varchar(4))
insert [memberdetails]
select 1,'张','效益' union all
select 2,'里','说客' union all
select 3,'我','我们' union all
select 3,'是','速度'

if object_id('[category]') is not null drop table [category]
go
create table [category]([categoryid] int,[category] varchar(5))
insert [category]
select 1,'科幻' union all
select 2,'动作' union all
select 3,'APIAN'


if object_id('[favcategory]') is not null drop table [favcategory]
go
create table [favcategory]([categoryid] int,[memberid] int)
insert [favcategory]
select 1,1 union all
select 1,2 union all
select 2,3 union all
select 2,4 union all
select 3,4

SELECT B.category, A.firstname, A.lastname
FROM memberdetails A INNER JOIN favcategory C ON A.memberid = C.memberid
             INNER JOIN category B ON C.categoryid = B.categoryid
WHERE B.category = '动作'


DROP TABLE memberdetails
DROP TABLE category
DROP TABLE favcategory
--测试结果:
/*
category firstname lastname 
-------- --------- -------- 
动作       我         我们
动作       是         速度

（所影响的行数为 2 行）

*/