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R - Concatenate two dataframes?
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if you're rbind is coming from base for some strange reason: I used rbind.data.frame
– Boern
May 2 '18 at 12:42
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What is sharding and why is it important?
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Sharding is just another name for "horizontal partitioning" of a database. You might want to search for that term to get it clearer.
From Wikipedia:
Horizontal partitioning is a design principle whereby rows of a database table are held separately, rather than splitting by columns (as for...
Null coalescing in powershell
... 'Unknown' -ne $null)[0] | Write-Output
Explanation
This explanation is based on an edit suggestion from an anonymous user. Thanks, whoever you are!
Based on the order of operations, this works in following order:
The , operator creates an array of values to be tested.
The -ne operator filter...
Is a Python dictionary an example of a hash table?
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Yes. Internally it is implemented as open hashing based on a primitive polynomial over Z/2 (source).
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How to design a database for User Defined Fields?
...clarative
referential
integrity is rarely out-performed by
trigger-based or application level
constraint enforcement.
Cons:
This could create a lot of tables.
Enforcing schema separation and/or a
naming convention would alleviate
this.
There is more application code
needed to operate...
How do I get the user agent with Flask?
...ser_agent object which contains the following attributes which are created based on the useragent string:
platform (windows, linux, macos, etc.)
browser (chrome, firefox, msie, etc.)
version
language
string (== request.headers.get('User-Agent'))
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How do I alter the position of a column in a PostgreSQL database table?
... the PostgreSQL Wiki says:
PostgreSQL currently defines column
order based on the attnum column of
the pg_attribute table. The only way
to change column order is either by
recreating the table, or by adding
columns and rotating data until you
reach the desired layout.
That's pretty...
Importing Maven project into Eclipse
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this is actually the most recommend solution as it is based on the maven pom-configuration and not on the derived, possibly outdated eclipse .project config
– hotzen
Jul 20 '16 at 7:21
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How to change Vagrant 'default' machine name?
...en 'default'. This is the name vagrant outputs on the console. Simplifying based on zook's (commenter) input
Set Provider Name
Vagrant.configure('2') do |config|
config.vm.box = "precise64"
config.vm.box_url = "http://files.vagrantup.com/precise64.box"
config.vm.provider :virtualbox do ...
best way to preserve numpy arrays on disk
...iles if they just know the shape, data type and whether it's row or column based. If you're just using Python then npy is fine, probably a little easier than binary.
– Mark
Jun 2 '17 at 19:36
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