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How to remove array element in mongodb?
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Is there call back with this?
– Oliver Dixon
Sep 1 '15 at 17:34
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How do I get only directories using Get-ChildItem?
I'm using PowerShell 2.0 and I want to pipe out all the subdirectories of a certain path. The following command outputs all files and directories, but I can't figure out how to filter out the files.
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Converting string from snake_case to CamelCase in Ruby
...equire "active_support/core_ext/string" is suffice, providing Rails is installed already.
– Masa Sakano
Jun 23 '18 at 2:03
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How to reshape data from long to wide format
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The reshape comments and similar argument names aren't all that helpful. However, I have found that for long to wide, you need to provide data = your data.frame, idvar = the variable that identifies your groups, v.names = the variables that will become multiple columns in wide f...
Best practices for in-app database migration for Sqlite
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I maintain an application that periodically needs to update a sqlite database and migrate old databases to the new schema and here's what I do:
For tracking the database version, I use the built in user-version variable that sqlite provides (sqlite does nothing w...
Django-Admin: CharField as TextArea
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Starting from Django 1.7 you need to add also fields = '__all__' under class Meta:.
– skoll
May 4 '16 at 11:43
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Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...rst time you iterate over it. For example, this will print the headline of all entries in the database:
for e in Entry.objects.all():
print e.headline
So your ten million rows are retrieved, all at once, when you first enter that loop and get the iterating form of the queryset. The wait ...
pass post data with window.location.href
...n attribute of the form to the URL and the method attribute to POST, then call the submit method on the form tag.
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Select unique or distinct values from a list in UNIX shell script
...n the following input:
class
jar
jar
jar
bin
bin
java
uniq will output all lines exactly once:
class
jar
bin
java
uniq -d will output all lines that appear more than once, and it will print them once:
jar
bin
uniq -u will output all lines that appear exactly once, and it will print them ...
How to execute PHP code from the command line?
...CLI SAPI. Try php-cli, maybe it's a package or a command available in your OS.
If you do see that your php command uses the CLI (Command Line Interface) SAPI (Server API), then run php -h | grep code to find out which crazy switch - as this hasn't changed for year- allows to run code in your versio...