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How do I execute inserts and updates in an Alembic upgrade script?

...s is useful for simple migrations. Use the models and session as you normally would in your application. """create teams table Revision ID: 169ad57156f0 Revises: 29b4c2bfce6d Create Date: 2014-06-25 09:00:06.784170 """ revision = '169ad57156f0' down_revision = '29b4c2bfce6d' from alembic imp...
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What are best practices for validating email addresses on iOS 2.0

... ; "]", or "\" Yes, that means +, ', etc are all legit. share | improve this answer | follow | ...
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What are the details of “Objective-C Literals” mentioned in the Xcode 4.4 release notes?

...ew ObjC literals were discussed in multiple WWDC 2012 sessions. I intentionally didn't remove the the filenames and the time of each slide so you can find them for yourself if you feel like. They are essentially the same thing as stated in this post, but there are also a few new things that I'll me...
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Could not locate Gemfile

...application on my server using Ruby, Gems, and Bundler. I am trying to install another Ruby on under a different user account but on the same VPS. When I go to run ...
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What does new self(); mean in PHP?

... the parent class The first situation would look like this (I've removed all non-necessary code, for this example -- you'll have to add it back to get the singleton behavior)* : class MyParentClass { } class MyChildClass extends MyParentClass { public static function getInstance() { ...
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python pandas remove duplicate columns

...he given example, the returned value would be [False,False,True]. Pandas allows one to index using boolean values whereby it selects only the True values. Since we want to keep the unduplicated columns, we need the above boolean array to be flipped (ie [True, True, False] = ~[False,False,True]) F...
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Determine whether an array contains a value [duplicate]

... } return index; }; } return indexOf.call(this, needle) > -1; }; You can use it like this: var myArray = [0,1,2], needle = 1, index = contains.call(myArray, needle); // true CodePen validation/usage ...
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Multi-Line Comments in Ruby?

.....is kinda ugly and creates a String instance, but I know one guy with a Smalltalk background, who does this." puts "Hello world!" ## # most # people # do # this __END__ But all forgot there is another option. Only at the end of a file, of course. This is how it looks (via screenshot) - othe...
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Python: split a list based on a condition?

What's the best way, both aesthetically and from a performance perspective, to split a list of items into multiple lists based on a conditional? The equivalent of: ...
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RegEx for Javascript to allow only alphanumeric

I need to find a reg ex that only allows alphanumeric. So far, everyone I try only works if the string is alphanumeric, meaning contains both a letter and a number. I just want one what would allow either and not require both. ...