how to get records from table with uniq on two columns - rails

Question

I'm trying to fetch records from database that should be uniqued by two attributes example

id name value

1 dog 4

2 dog 4

3 cat 5

4 cat 4

I want the result to be

id name value

1 dog 4

3 cat 5

4 cat 4

so the data has been uniqued by value and name , I've tried many ways with ruby to do but with no luck

Answer 1

You can use group by :

select min(id) as id, name, value
from table t
group by name, value;

Answer 2

it worked with group method of rails

table.all.group('value, name') 

the generated query is

select * from table t group by value, name