Template
single collection
multiple collections
mgodatagen
update
indexe
explain
Stage
Database
bson
mgodatagen
[{"_id":1,"value":"Apple"},{"_id":2,"value":"APPLE"},{"_id":3,"value":"Boy"}]
Query
db.collection.find({$expr:{$eq:[{$toLower:"$value"},{$toLower:"apple"/** your search string here*/}]}})
Result