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Twitter stuff
http://krysmann.nl/wp/index.php/2017/09/07/twitter-stuff/

Twitter stuff Visit the post for more.

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http://krysmann.nl/wp/index.php/2017/09/07/start-up/

Start up Links

Maps
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Maps Visit the post for more.

db.mqtt.find({topic:"rrd/srt"}).forEach(function(doc){ db.subset.insert(doc); });

http://krysmann.net/wordpress/?p=62610

Mongodb -save subset of query to new collection db.mqtt.find({topic:”rrd/srt”}).forEach(function(doc){ db.subset.insert(doc); });

Following query will count occurance of users: db.tweets.aggregate([ { $group: { _id: '$user.screen_name', count: {$sum: 1} }}, {$sort: { count: -1 }} ], {allowDiskUse: true}); Note the option allowDiskUse is needed if error: { "code" : 16819, "errmsg" : "Sort exceeded memory limit of 104857600 bytes, but did not opt in to external sorting. Aborting operation. Pass allowDiskUse:true to opt in.", [ 26 more words. ]

http://krysmann.net/wordpress/?p=62606

Mongodb Twitter count users (allowDiskUse) Following query will count occurance of users: db.tweets.aggregate([ { $group: { _id: ‘$user.screen_name’, count: {$sum: 1} }}, {$sort: { count: -1 }} ], {allowDiskUse: true}); Note the…

Copying selection where field date == 20120105 to new collection subset. If subset not exists then it will be created. db.my_collection.find({date:"20120105"}).forEach(function(doc){ db.subset.insert(doc); });

http://krysmann.net/wordpress/?p=62601

Copy MongoDB selection to another collection Copying selection where field date == 20120105 to new collection subset. If subset not exists then it will be created. db.my_collection.find({date:”20120105″}).forEach(function(doc){ db…

Source: db.tweets.find().sort({_id:-1}).limit(1).forEach(function (doc){ print(doc._id.getTimestamp()) }) will return timestamp of most recent record in following format: Tue May 03 2016 08:29:06 GMT+0200 (CEST)

http://krysmann.net/wordpress/?p=62597

Convert Mongo _id to datetime Source:  db.tweets.find().sort({_id:-1}).limit(1).forEach(function (doc){ print(doc._id.getTimestamp()) }) will return timestamp of most recent record in following format: Tue May 03 2016 08:29:06 …