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Ruby on Rails: How do I add a not null constraint to an existing column using a migration?
In my Rails (3.2) app, I have a bunch of tables in my database but I forgot to add a few not null constraints. I've googled around but I can't find how to write a migration which adds not null to an existing column.
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How do I clear this setInterval inside a function?
Normally, I’d set the interval to a variable and then clear it like var the_int = setInterval(); clearInterval(the_int); but for my code to work I put it in an anonymous function:
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Emacs mode for Stack Overflow's markdown
I am using Org-mode in Emacs to handle all my technical documentation. I would like to use Emacs to prepare questions that I have for Stack Overflow. Is there an Emacs mode for that, or even better, an extension for Org-mode to handle Stack Overflow formatting? Ideally it should include all formatti...
Using sed and grep/egrep to search and replace
I am using egrep -R followed by a regular expression containing about 10 unions, so like:
.jpg | .png | .gif etc. This works well, now I would like to replace all strings found with .bmp
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C/C++ NaN constant (literal)?
Is this possible to assign a NaN to a double or float in C/C++? Like in JavaScript you do: a = NaN . So later you can check if the variable is a number or no.
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Is it safe to remove selected keys from map within a range loop?
How can one remove selected keys from a map?
Is it safe to combine delete() with range, as in the code below?
4 Answers
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JavaScript moving element in the DOM
Let's say I have three <div> elements on a page. How can I swap positions of the first and third <div> ? jQuery is fine.
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How can I change Mac OS's default Java VM returned from /usr/libexec/java_home
(Wasn't sure if this should go on SU... migration is certainly an option, but more programmers read questions here, so here goes).
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Swapping two variable value without using third variable
One of the very tricky questions asked in an interview.
27 Answers
27
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Get Image size WITHOUT loading image into memory
I understand that you can get the image size using PIL in the following fashion
6 Answers
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