Will it automatically add index to forien_keys?

Rails
1

has_may ,belongs_to ,etc
in those Model association ,will it automatically add index to
forien_keys ?

2

Pokkai D. wrote:

has_may ,belongs_to ,etc
in those Model association ,will it automatically add index to
forien_keys ?

no, you need to use the
add_index :table, :column_name
in your migrations