CODEWITHSUNDEEP
ruby-on-railsrubymodel
enamul17
enamul17

Reputation: 159

How to return distinct rows in rails?

I have a model Program containing fields program_title, department_id and date. I have inserted two rows having same program title and date but different department_id.

Insert into programs(program_title,date,department_id) Values ("prog1","4/2/2017","1");
Insert into programs(program_title,date,department_id) Values ("prog1","4/2/2017","2");

Now I want to return rows which will be distinct by program_title whatever be the department_id. I have tried,

@event_contents=Program.select(:id,:date,:program_title).distinct(:program_title)

But still it returns both the rows. Any help is appreciated.

Upvotes: 2

Views: 93

Answers (2)

Mayank
Mayank

Reputation: 727

Try this

Program.all.distinct(:program_title).pluck( :id,:program_title,:date)

It will return data as array of elements though

Hope it helps

Upvotes: 0

Drenmi
Drenmi

Reputation: 8787

SQL can only collapse rows where all values are the same when using DISTINCT. Because you are selecting id, which is different for every record, the rows are not distinct. E.g.:

---------------------------------
| id | program_title | date     |
---------------------------------
|  1 | prog1         | 4/2/2017 |
|  2 | prog1         | 4/2/2017 |
---------------------------------

You'll need to exclude the id from your #select for it to work:

Program.select(:date, :program_title).distinct

Upvotes: 2

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