将一组数据的合并和数据中特殊字符的替换

目标结果返回数据

"filmId":"1",
"filmName":"我不是药神",
"filmLength":"132",
"filmCats":"喜剧,剧情",
"actors":"程勇,曹斌,吕受益,刘思慧",
"imgAddress":"films/238e2dc36beae55a71cabfc14069fe78236351.jpg",
"subAddress":"films/001.jpg,films/002.jpg,films/003.jpg,films/004.jpg,films/005.jpg"

涉及到的表

表一  主要电影信息表 mooc_film_t

 表二：次要电影信息表 mooc_film_info_t

 表三 ：演员表 电影id对应的演员 mooc_film_actor_t

 表四 电影id对应的电影类型 mooc_cat_dict_t

 第一步，使用表一表二凑出部分数据

 select 
 film.UUID as filmId,
 film.film_name as filmName,
 info.film_length as filmLength,
 film.film_cats as film_cats,
 film.img_address as imgAddress,
 info.film_imgs as subAddress
 from mooc_film_t film LEFT JOIN mooc_film_info_t  info on
 film.UUID = info.film_id

运行结果

 第二步 ：查询出演员

select * from mooc_film_actor_t

#将多个字段合成一个
select GROUP_CONCAT(role_name SEPARATOR ',') from mooc_film_actor_t where film_id = 2

 则第一步的结果改为

select 
 film.UUID as filmId,
 film.film_name as filmName,
 info.film_length as filmLength,
 film.film_cats as film_cats,
  (select GROUP_CONCAT(role_name SEPARATOR ',') from mooc_film_actor_t actor 
	where actor.film_id = film.UUID) as actors,
 film.img_address as imgAddress,
 info.film_imgs as subAddress
 from mooc_film_t film LEFT JOIN mooc_film_info_t  info on
 film.UUID = info.film_id

　　

 第三步将电影类型转换为对应数据

3.1 将#替换为，

select 
REPLACE(TRIM(BOTH '#' FROM film.film_cats),"#",",")
from mooc_film_t film

3.2将数字替换为关联表中的数据 mooc_film_t ，mooc_cat_dict_t

#获取到id 所对应的值

select
*
from mooc_cat_dict_t cat
where FIND_IN_SET(cat.UUID,(select REPLACE(TRIM(BOTH '#' FROM film.film_cats),"#",",")
FROM mooc_film_t film
)
)

 把文字合并

#把值连接起来
  select
 GROUP_CONCAT(show_name SEPARATOR ',')
 from mooc_cat_dict_t cat
 where FIND_IN_SET(cat.UUID,(select REPLACE(TRIM(BOTH '#' FROM film.film_cats),"#",",")
                                                            FROM mooc_film_t film
  )
 )

 最终

select 
 film.UUID as filmId,
 film.film_name as filmName,
 info.film_length as filmLength,
  (  select
 GROUP_CONCAT(show_name SEPARATOR ',')
 from mooc_cat_dict_t cat
 where FIND_IN_SET(cat.UUID,(select REPLACE(TRIM(BOTH '#' FROM film.film_cats),"#",",")
                                                            FROM mooc_film_t film
  )
 )) as filmCats,
  (select GROUP_CONCAT(role_name SEPARATOR ',') from mooc_film_actor_t actor 
    where actor.film_id = film.UUID) as actors,
 film.img_address as imgAddress,
 info.film_imgs as subAddress
 from mooc_film_t film LEFT JOIN mooc_film_info_t  info on
 film.UUID = info.film_id