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How do you write a migration to rename an ActiveRecord model and its table in Rails?
I'm terrible at naming and realize that there are a better set of names for my models in my Rails app. Is there any way to use a migration to rename a model and its corresponding table?
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Java heap terminology: young, old and permanent generations?
I'm trying to understand What the concepts of young , old and permanent generations are in the Java heap terminology, and more specifically the interactions between the three generations.
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How to find the JVM version from a program?
I want to write a sample Java file in which I want to know the JVM version in which the class is running. Is there a way?
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Are class names in CSS selectors case sensitive?
...e generally case-insensitive; this includes class and ID selectors.
But HTML class names are case-sensitive (see the attribute definition), and that's causing a mismatch in your second example. This has not changed in HTML5.1
This is because the case-sensitivity of selectors is dependent on what t...
How to install pip with Python 3?
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edit: Manual installation and use of setuptools is not the standard process anymore.
If you're running Python 2.7.9+ or Python 3.4+
Congrats, you should already have pip installed. If you do not, read onward.
If you're running a Un...
Django get the static files URL in view
I'm using reportlab pdfgen to create a PDF. In the PDF there is an image created by drawImage . For this I either need the URL to an image or the path to an image in the view. I managed to build the URL but how would I get the local path to the image?
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When to add what indexes in a table in Rails
... would be better, because it accelerates the search in sorting in this column. And Foreign keys are something searched for a lot.
Since Version 5 of rails the index will be created automatically, for more information see here.
Should I add "index" to the automatically created "id" column?
No,...
Bash variable scope
Please explain to me why the very last echo statement is blank? I expect that XCODE is incremented in the while loop to a value of 1:
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Difference between CC, gcc and g++?
What are the difference between the 3 compilers CC, gcc, g++ when compiling
C and C++ code in terms of assembly
code generation, available libraries, language features, etc.?
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How to run test cases in a specified file?
My package test cases are scattered across multiple files, if I run go test <package_name> it runs all test cases in the package.
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