Group activity items

Question

I have the following table structure for storing activity items

id, trackable_id, trackable_type, owner_id, owner_type

where trackable_id and trackable_type tells me on what object(entity) the action is performed on. For example if a User with id=1 likes a Picture with id=1

id, trackable_id, trackable_type, owner_id, owner_type

1,       1,            Picture,      1,        User

Similarly another user can like the same picture. In my news feed, I can easily display the activities performed by the users, however I would like to achieve something like this:

John and katy likes Picture.

instead of

John likes Picture
Kay  likes Picture.

I guess the way to go is to do a group by based on trackable_id and trackable_type but it returns me one row(expected result of group by). I have not used group_concat before, does it help in this kind of situation? Thanks!

Nisarg · Answer 1 · 2013-07-23T07:23:10.903

2

Hey you can use Like this

CONCAT(GROUP_CONCAT( user_name SEPARATOR 'AND' ),' LIKES PICTURES')

Demo

edited Jul 23 '13 at 07:23

answered Jul 23 '13 at 07:17

Nisarg

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score 0 · Answer 2 · edited May 23 '17 at 12:03

0

Yes it helps.

Refer this

GROUP_CONCAT(columnName SEPARATOR ' AND ')

edited May 23 '17 at 12:03

Community

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answered Jul 23 '13 at 06:54

Akhil

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Konstantin Rudy · Answer 3 · 2013-07-23T07:07:36.250

0

Looks like you are using polymorfic associations (if no - then you should be using it). Your method will look like the following:

def liked_by_string
  user_names = users.collect(&:name).to_sentence # => "John, Katty, Mark and Pete"

  "#{user_names} like the Picture"      
end

edited Jul 23 '13 at 07:07

answered Jul 23 '13 at 07:00

Konstantin Rudy

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Group activity items

3 Answers3