MongoDB University M201
An index covers a query only when both all fields in the query are a part of the index and all the fields are turned in the result are in the same index.
ๆญฃ่ฆ่กจ้ๅผๅฆๆๆๆๅฎ้้ ญๆๆฏ่ผๆๆ็
Mongodb will be grouping documents and comparing their fields based on different BSON types using a specific comparsion order
index usage
Memory Constraints
RealTime Processing
Batch Processing
Results are subject to 16MB document limit
100MB of RAM per pipeline Stage