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What are the differences between B trees and B+ trees?
...e work and more disk reads which makes sense because the tree has all this extra data in it. I don't get it.
– Eric
Sep 2 '15 at 2:45
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How to determine the current shell I'm working on
...nd that if you do this from within a subshell then it can lead to spurious extra lines by matching the parent's PID as well as the actual shell process. For this, I use -q instead of -p: SHELL=$(ps -ocomm= -q $$)
– Steve
Dec 28 '17 at 23:09
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How can I check if a directory exists in a Bash shell script?
...e variable, like if [ -d "${THING:+$THING/}" ]. A directory won't mind the extra slash. A file will evaluate to false. Empty will remain empty, so false. And a symlink will be resolved to its destination. Of course, it depends on your goal. If you want to go there, this is fine. If you want to delet...
What is the non-jQuery equivalent of '$(document).ready()'?
...eive DOM ready, without jQuery, you might check into this library. Someone extracted just the ready part from jQuery. Its nice and small and you might find it useful:
domready at Google Code
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How does an underscore in front of a variable in a cocoa objective-c class work?
...ng more than a common convention, but a useful one), then you need to do 1 extra thing so the auto-generated accessor (for the property) knows which ivar to use. Specifically, in your implementation file, your synthesize should look like this:
@synthesize missionName = _missionName;
More generic...
Indent multiple lines quickly in vi
...er summarises the other answers and comments of this question, and it adds extra information based on the Vim documentation and the Vim wiki. For conciseness, this answer doesn't distinguish between Vi and Vim-specific commands.
In the commands below, "re-indent" means "indent lines according to yo...
HTML text input field with currency symbol
...th content: '$' on inputs and adding an absolutely positioned element adds extra html - I like do to a background SVG inline css.
It goes something like this:
input {
width: 85px;
background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' version='1.1' heigh...
What is wrong with using goto? [duplicate]
...urn can be used instead of goto to jump out of nested loops. For example, extract the nested loops into a new function and return from there when the condition that triggers the goto is satisfied. I only see goto being used only to get an extra bit of performance
– mljrg
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When to Redis? When to MongoDB? [closed]
...lets you give it a key and look up a single value. Redis itself can store strings, lists, hashes, and a few other things; however, it only looks up by name.
Cache invalidation is one of computer science's hard problems; the other is naming things. That means you'll use Redis when you want to avoi...
How do I clear the std::queue efficiently?
...anyway when getting destroyed. So the accepted answer is O(n) plus it does extra allocations and initializations for brand new queue.
– Shital Shah
Dec 2 '16 at 1:08
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