Mysql user subscription query fails - php

Question

I have a database named socialnetwork and has 5 tables category , post_category , posts , subscribe , user.
my table structures
-------- -------------
category posts
-------- ------------
categoryID postID
categoryName post
userID
categoryID
-------------- ---------------
post_category subscribe
--------------- ---------------
postID subscriberID
categoryID categoryID
--------------
usertable
--------------
userID
userName
data's in the table
category table usertable
-------------------------- -------------------
categoryID categoryName userID userName
--------------------------- --------------------
1 film 1 jijojohn32
2 television 2 sijojohn
posts_category table subscribe table
------------------ -------------------------
postID categoryID subscriberID categoryID
--------------------- ------------------------
1 1 1 1
1 2 1 2
2 2 2 2
posts table
---------------------------------------------------
postID post userID categoryID
--------------------------------------------------
1 this post is cool 1 1
2 demo post 2 2
User 1 can subscribe to different categories and he can see the articles in the categories he subscribes. That's what i am trying to implement here. And i have this query but it's not giving me the result i want.
USE socialnetwork;
SELECT socialnetwork.usertable.userName,socialnetwork.posts.post, GROUP_CONCAT(socialnetwork.category.categoryName) as category
FROM socialnetwork.category
INNER JOIN subscribe
ON subscribe.categoryID = category.categoryID
INNER JOIN posts
ON posts.categoryID = subscribe.categoryID
INNER JOIN usertable
ON usertable.userID = posts.userID
INNER JOIN socialnetwork.post_category
ON post_category.postID = posts.postID
WHERE subscriberID = "1"
GROUP BY socialnetwork.category.categoryName
Here's the result i am getting
---------------------------------
username post category
----------------------------------
jijojohn32 this post is cool film, film
sijojohn demo post television
The result i want
---------------------------------------------
username post category
-------------------------------------------
jijojohn32 this post is cool film,television
sijojohn demo post television
I want the post from the categories he subscribed to , the username of the user posted the articles , and categories which posts reside. What's wrong in my query ?. any idea ?. thanks

Answer 1

You are not aggregating by the right columns. I think this is the query that you want:
SELECT ut.userName, p.post, GROUP_CONCAT(c.categoryName) as category
FROM socialnetwork.category c INNER JOIN
subscribe s
ON s.categoryID = c.categoryID INNER JOIN
posts p
ON p.categoryID = s.categoryID INNER JOIN
usertable ut
ON ut.userID = p.userID INNER JOIN
socialnetwork.post_category pc
ON pc.postID = p.postID
WHERE subscriberID = 1
GROUP BY ut.userName, p.post;

Answer 2

Here's the working query. I made some modifications in the table. Deleted the categoryID from posts. Made a new table called post_category.
--------------
post_category
-------------
postID
categoryID
Here's the query
SELECT GROUP_CONCAT(category.categoryName) as category , category.categoryID , subscribe.subscriberID , posts.post ,
usertable.userName
from category
INNER JOIN subscribe
ON subscribe.categoryID = category.categoryID
INNER JOIN post_category
ON category.categoryID = post_category.categoryID
INNER JOIN posts
ON posts.postID = post_category.postID
INNER JOIN usertable
ON usertable.userID = posts.userID
WHERE subscriberID = 1
GROUP BY post_category.postID

Answer 3

There exists a conflict
Category table consists of
Category id and Category Name
Post Table consists of
Post id and Corresponding Category Id
As well as
Post_Category table consists of
Post id and Category Id
Hence it is picking from the Posts table, that
Row 1 - has only 1 category id associated with it
I suggest you remove Category id from Posttable
It is pointless to have 2 keys in 1 table, and similar 2 keys in other table.
Try to establish Primary key Foreign key relationship.
Hope that helps