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MySQL vs MongoDB 1000 reads
...nary json document)
So a b-tree lookup, and a binary page read. Log(n) + 1 IOs. If the indexes can reside entirely in memory, then 1 IO.
In MySQL with 20 tables, you have to perform:
One index lookup on the root table (again, assuming the entity is fetched by id)
With a clustered index, we can ...
How do I convert an enum to a list in C#? [duplicate]
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Get PostGIS version
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edited Mar 28 '13 at 20:19
Brad Koch
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Android - border for button
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Step 1 : Create file named : my_button_bg.xml
Step 2 : Place this file in res/drawables.xml
Step 3 : Insert below code
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/and...
How to set a timer in android
...not change the UI)?
Use this the Java way:
http://docs.oracle.com/javase/1.5.0/docs/api/java/util/Timer.html
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How to check if an email address exists without sending an email?
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Create new user in MySQL and give it full access to one database
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edited Jan 3 '18 at 14:11
Flimm
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Pry: show me the stack
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Use the pry-stack_explorer plugin, it allows you to move up and down the call-stack (with up and...
How can I rename a field for all documents in MongoDB?
...d:x._id}, {$set:{"name.last":x.name.additional}, $unset:{"name.additional":1}});
}
}
db.foo.find().forEach(remap);
In MongoDB 3.2 you can also use
db.students.updateMany( {}, { $rename: { "oldname": "newname" } } )
The general syntax of this is
db.collection.updateMany(filter, update, optio...