Dex, the Index Bot
Dex is a MongoDB performance tuning tool that compares queries to the available indexes in the queried collection(s) and generates index suggestions based on simple heuristics. Currently you must provide a connection URI for your database.
Dex uses the URI you provide as a helpful way to determine when an index is recommended. Dex does not take existing indexes into account when actually constructing its ideal recommendation.
Currently, Dex only recommends complete indexes, not partial indexes. Dex ignores partial indexes that may be used by the query in favor of a better index, if one is not found. Dex recommends partially-ordered indexes according to a rule of thumb:
Your index field order should first answer:
- Equivalent value checks
- Sort clauses
- Range value checks ($in, $nin, $lt/gt, $lte/gte, etc.)
Note that your data cardinality may warrant a different order than the suggested indexes.