From Wikipedia, it sounds like the time to use it is when: - You have enough a huge amount of data (hundreds of millions or more rows) - You want to index a c

From Wikipedia, it sounds like the time to use it is when: - You have enough a huge amount of data (hundreds of millions or more rows) - You want to index a column whose values are never changed, and are monotonically increasing (e.g. a created_at datetime field).