Storing Streaming Data - Real-Time Analytics - page 240

"nChunkSkips" : 0,
"millis" : 2,
" indexBounds" : {
"customer_id" : [
[
1,
1
]
],
"ts" : [
[
ISODate("2013-12-01T08:00:00Z"),
ISODate("0NaN-NaN-NaNTNaN:NaN:NaNZ")
]
]
}
}
Of course, the old customer_id index is still used by the original
customer query:
> db.metrics.find({customer_id:1}).explain()
{
"cursor" : "BtreeCursor customer_id_1",
"isMultiKey" : false,
"n" : 1,
"nscannedObjects" : 1,
"nscanned" : 1,
"nscannedObjectsAllPlans" : 1,
"nscannedAllPlans" : 1,
"scanAndOrder" : false,
"indexOnly" : false,
"nYields" : 0,
"nChunkSkips" : 0,
"millis" : 3,
" indexBounds" : {