Ruby/Rails: Merge result of map

Question

I have @products collection and I want to merge image_ids to single array. Here is the output of @products.map(&:image_ids):

@products.map(&:image_ids)
=> [[1654, 1655, 1656],
 [1649, 1650, 1652, 1653],
 [1625],
 [1624],
 [1623],
 [1622],
 [1621],
 [1620],
 [1619],
 [1618]]

Answer 1

Do as below using flat_map :

@products.flat_map(&:image_ids)