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copied!<p>Ok, that looks pretty good. Let's construct some of the queries.</p> <p>Assuming the collections are named users, events, venues:</p> <ul> <li><p><strong>Insert some dummy events</strong>:</p> <blockquote> <p>db.events.insert({tags:["awesome","fun","cool"]})</p> <p>db.events.insert({tags:["sweet","fun","rad"]})</p> </blockquote></li> <li><p><strong>Make an index</strong> (like a boss)</p> <blockquote> <p>db.events.ensureIndex({ tags: 1 })</p> </blockquote></li> <li><p><strong>Listing of distinct tags (this might be hard given current design)</strong>:</p> <p>Nope, not hard.</p> <blockquote> <p>db.events.distinct("tags")</p> </blockquote> <p>[ "awesome", "cool", "fun", "rad", "sweet" ]</p></li> <li><p><strong>Events in a given tag</strong> (you meant "with a given tag" right?)</p> <blockquote> <p>db.events.find({tags: "fun"})</p> </blockquote> <p>{ "_id" : ObjectId("4ecc08c62477605df6522c97"), "tags" : [ "awesome", "fun", "cool" ] }</p> <p>{ "_id" : ObjectId("4ecc08d92477605df6522c98"), "tags" : [ "sweet", "fun", "rad" ] }</p></li> <li><p><strong>Event information along with venue location</strong></p> <p>You can do this a couple different ways. One way would be to query for the event and subsequently query for the venue. With both documents, join (combine) the data you want manually.</p> <p><strong>OR</strong></p> <p>You can denormalize a bit and store cached venue names + locations (but not venue details like hours of operation, max occupancy, website, phone number, etc..) for a speed boost (1 query instead of 2) That method comes with the standard denormalization caveat of not being able to update your data in one place.</p></li> <li><p><strong>All event and venue information for a particular event</strong></p> <p>See above</p></li> <li><p><strong>All events near me. Need to use a geo index on loc</strong></p> <p>Two queries again, same concept as above just reverse the order.</p> <p>Get the venues:</p> <blockquote> <p>db.venues.find( { loc : { $near : [lat,lon] } } )</p> </blockquote> <p>Get the events using the venue ids:</p> <blockquote> <p>db.events.find( { venue : { $in : [id1,id2,id3...] } } )</p> </blockquote></li> </ul> <p>Some of this stuff can be done automatically for you if you use an ODM.</p> <p>Good luck!</p>

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