ways to select values by keys list?

Question

For example I have key structure entity:product:[id] where id - is an integer [0-n]

So I can use this keys entity:product:* but I don't how much load does this query to the redis server.

Another solution is

1. Create one list key that will store Ids of the entity:products.

   RPUSH entity:products:ids 1 
   RPUSH entity:products:ids 2
   RPUSH entity:products:ids 3
   RPUSH entity:products:ids 4
   

2. And then (pseudo-code)

   entityProducts = redis.LRANGE('entityLproducts:ids, 0, -1)
   
   foreach (entityProducts as id)
   {
       redis.GET('entity:product:' + id)
   }
   

What is the better way? What will be faster and what will do less load to the redis server?