m102-hw3.1.md

HOMEWORK: HOMEWORK 3.1

Start a mongod server instance (if you still have a replica set, that would work too).

Next, download the handout and run:

mongo --shell localhost/performance performance.js
homework.init()

Build an index on the "active" and "tstamp" fields. You can verify that you've done your job with

db.sensor_readings.getIndexes()

When you are done, run:

homework.a()

and enter the numeric result below (no spaces).

Note: if you would like to try different indexes, you can use db.sensor_readings.dropIndexes() to drop your old index before creating a new one. (For this problem you will only need one index beyond the _id index which is present by default.)

db.sensor_readings.createIndex({tstamp: 1, active: 1})
homework.a()
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