Indexes
Indexes are per collection
- B-tree indexes
- _id is indexed (and unique)
- Single Field
- Compund-key indexes
- Multi-key indexes (indexing each element of an array)
- Geospatial Index
- Text Indexes (beta)
If there is an array of values (eg. tags) then the specific document will be indexed by each one of the values in that array. "Fake full-text indexing."