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Is there a standard for storing normalized phone numbers in a database?
...s flexible enough to handle international numbers, and also something that allows the various parts of the number to be queried efficiently.
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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...
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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What is `related_name` used for in Django?
... back to your model.
If you don't specify a related_name, Django automatically creates one using the name of your model with the suffix _set, for instance User.map_set.all().
If you do specify, e.g. related_name=maps on the User model, User.map_set will still work, but the User.maps. syntax is ob...
How do I determine the target architecture of static library (.a) on Mac OS X?
...cutable ppc
Example with archive:
logan:/Users/logan% file /usr/lib/libMallocDebug.a
/usr/lib/libMallocDebug.a: Mach-O universal binary with 2 architectures
/usr/lib/libMallocDebug.a (for architecture i386): current ar archive random library
/usr/lib/libMallocDebug.a (for architecture ppc): ...
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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Where is my .vimrc file?
I have been using Vim , and I would really like to save my settings. The problem I am having is that I cannot find my .vimrc file, and it is not in the standard /home/user/.vimrc location. How might I find this file?
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How do I auto-hide placeholder text upon focus using css or jquery?
This is done automatically for every browser except Chrome .
26 Answers
26
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libxml/tree.h no such file or directory
...wered Sep 15 '09 at 18:21
Matt BallMatt Ball
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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...