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Rails: around_* callbacks
...api.rubyonrails.org/classes/ActiveRecord/Callbacks.html , but don't understand when the around_* callbacks are triggered in relation to before_* and after_* .
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MySQL: What's the difference between float and double?
...ndering why, I checked the mysql documentation, but honestly didn't understand what the difference is.
6 Answers
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How do I declare and assign a variable on a single line in SQL
...at the ' is escaped by doubling it to ''.
Since the string delimiter is ' and not ", there is no need to escape ":
DECLARE @var nvarchar(max) = '"My Name is Luca" is a great song';
The second example in the MSDN page on DECLARE shows the correct syntax.
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Twitter Bootstrap: div in container with 100% height
Using twitter bootstrap (2), I have a simple page with a nav bar, and inside the container I want to add a div with 100% height (to the bottom of the screen). My css-fu is rusty, and I can't work this out.
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Google Developer Tools “Network” Tab clears after redirect
Google Developer Tools "Network" Tab clears after redirect to another page and i want to know if there is any way to keep all request?
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jQuery.active function
... in the library, it seems to be there exclusively to support $.ajaxStart() and $.ajaxStop() (which I'll explain further), but they only care if it's 0 or not when a request starts or stops. But, since there's no reason to hide it, it's exposed to you can see the actual number of simultaneous AJAX r...
Vim: How to change the highlight color for search hits and quickfix selection
...ors/desert.vim. Color mappings are defined there with the hi[ghlight] command. The search highlighting is defined as
hi Search guibg=peru guifg=wheat
for the GUI and
hi Search cterm=NONE ctermfg=grey ctermbg=blue
for terminals.
You can override this setting in your .vimrc using the same com...
Difference between window.location.assign() and window.location.replace()
What is the difference between window.location.assign() and window.location.replace() , when both redirect to a new page?
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“git rm --cached x” vs “git reset head -- x”?
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There are three places where a file, say, can be - the tree, the index and the working copy. When you just add a file to a folder, you are adding it to the working copy.
When you do something like git add file you add it to the index. And when you commit it, you add it to the tree as well.
It ...
Ruby Arrays: select(), collect(), and map()
..., but a Hash. You can also use select here, but the block is given the key and value in this case:
irb(main):001:0> h = {:sku=>"507772-B21", :desc=>"HP 1TB 3G SATA 7.2K RPM LFF (3 .", :qty=>"", :qty2=>"1", :price=>"5,204.34 P"}
irb(main):002:0> h.select { |key, value| !value.em...