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Check if a table exists in Rails
I have a rake task that won't work unless a table exists. I'm working with more than 20 engineers on a website so I want to make sure they have migrated the table before they can do a rake task which will populate that respective table.
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How to make an unaware datetime timezone aware in python
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Why would someone use WHERE 1=1 AND in a SQL clause?
...d built at run time, you don't have to worry about whether you have one or more than one condition. You can generate them all like:
and <condition>
and concatenate them all together. With the 1=1 at the start, the initial and has something to associate with.
I've never seen this used for a...
Difference between “or” and || in Ruby? [duplicate]
...ore_them_in_the_cache
Sometimes, this can make control flow a little bit more fluent than using if or unless.
It's easy to see why in this case the operators have the "wrong" (i.e. identical) precedence: they never show up together in the same expression anyway. And when they do show up together,...
Why am I getting error for apple-touch-icon-precomposed.png
... I found a nice article that details everything I wanted to know (and more): mathiasbynens.be/notes/touch-icons
– Alexis
May 22 '13 at 15:02
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Remove all unused resources from an android project
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Capturing multiple line output into a Bash variable
...s (2) the unquoted version (echo $RESULT) replaces each sequence of one or more blanks, tabs and newlines with a single space. Thus (1) preserves the shape of the input variable, whereas (2) creates a potentially very long single line of output with 'words' separated by single spaces (where a 'word'...
How do I convert a dictionary to a JSON String in C#?
...ries) + "}";
}
But, if you are serializing several different classes, or more complex data structures, or especially if your data contains string values, you would be better off using a reputable JSON library that already knows how to handle things like escape characters and line breaks. Json.NET...
Signing a Windows EXE file
...ll endanger your users privacy. Look what happened with DELL. You can find more information for accomplishing this both in code and through Windows in:
Stack Overflow question Install certificates in to the Windows Local user certificate store in C#
Installing a Self-Signed Certificate as a Truste...
String Concatenation using '+' operator
...ou should use a StringBuilder for such cases. I have an article going into more details about the two which will hopefully answer further questions.
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