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perl -pe"s/foo/bar/g" file.txt Or in-place: perl -i -pe's/foo/bar/g' file.txt On Windows: perl -i.bak -pe"s/foo/bar/g" file.txt

Adding components one after another results in a UI that's hard to use, because the components all are somewhere. The components are ordered from top to bottom, each component in a separate "row". To remedy this and provide you as developer with a possibility to layout components easily S...

genRandom creates a stream of random numbers that has a one in four chance of terminating each time it's called. def genRandom: Stream[String] = { val random = scala.util.Random.nextFloat() println(s"Random value is: $random") if (random < 0.25) { Stream.empty[String] ...

curl -XGET 'http://www.example.com:9200/myIndexName/_count?pretty' Output: { "count" : 90, "_shards" : { "total" : 6, "successful" : 6, "failed" : 0 } } The index has 90 documents within it. Reference Link: Here

curl -XPUT 'www.example.com:9200/myIndexName?pretty' Output: { "acknowledged" : true } Reference Link: Here

curl -XDELETE 'http://www.example.com:9200/myIndexName?pretty' output: { "acknowledged" : true } Reference Link: Here

Before you compile your app and run it on your device, you'll need create some icons and splash screens, and add a mobile-config.js file to your app. App.icons({ // iOS 'iphone': 'resources/icons/icon-60x60.png', 'iphone_2x': 'resources/icons/[email protected]', 'ipad': 'resources/icons...

You'll need to separate out your application layer from your database layer, and that means specifying the MONGO_URL. Which means running your app through the bundle command, uncompressing it, setting environment variables, and then launching the project as a node app. Here's how... #make sure you...

There's two great utilities for black-box analysis of databases. First is variety.js, which will give you a high-level overview. The second is schema.js, which will let you dig into the collections for more detail on the individual fields. When inheriting a production Mongo database, these two util...

This command will create a /dump directory, and store each collection in a separate BSON blob file. This is the best way to backup or transfer databases between systems. mongodump --db meteor

Mongo supports database-to-database copying, which is useful if you have large databases on a staging database that you want to copy into a local development instance. // run mongod so we can create a staging database // note that this is a separate instance from the meteor mongo and minimongo ins...

Preallocation. Mongo sets aside disk-space in empty containers, so when the time comes to write something to disk, it doesn't have to shuffle bits out of the way first. It does so by a doubling algorithm, always doubling the amount of disk space preallocated until it reaches 2GB; and then each preal...

Did you know about the --url flag? Very handy. meteor mongo --url YOURSITE.meteor.com

They're not easily accessible. If you run the 'meteor bundle' command, you can generate a tar.gz file, and then run your app manually. Doing that, you should be able to access the mongo logs... probably in the .meteor/db directory. If you really need to access mongodb log files, set up a regular mo...

Gotta rotate those log files, or they'll eventually eat up all of your disk space. Start with some research... mongodb-log-file-growth rotate-log-files Log files can be viewed with the following command... ls /var/log/mongodb/ But to set up log-file rotation, you'll need to do the following.....

db.posts.find().forEach(function(doc){ if(doc.commenters){ var firstCommenter = db.users.findOne({'_id': doc.commenters[0]._id }); db.clients.update({_id: doc._id}, {$set:{'firstPost': firstCommenter }}, false, true); var firstCommenter = db.users.findOne({'_id': do...

db.posts.find().forEach(function(doc){ if(doc.commentsBlobId){ var commentsBlob = db.comments.findOne({'_id': commentsBlobId }); db.posts.update({_id: doc._id}, {$set:{'comments': commentsBlob }}, false, true); } });

db.posts.find().forEach(function(doc){ if(doc.foo === 'bar'){ db.posts.update({_id: doc._id}, {$set:{'foo':'squee'}}, false, true); } });

db.posts.find().forEach(function(doc){ if(doc._id){ db.posts.update({_id: doc._id}, {$set:{ timestamp: new Date(parseInt(doc._id.str.slice(0,8), 16) *1000) }}, false, true); } });

var timestamp = Math.floor(new Date(1974, 6, 25).getTime() / 1000); var hex = ('00000000' + timestamp.toString(16)).substr(-8); // zero padding var objectId = new ObjectId(hex + new ObjectId().str.substring(8));