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Python: List vs Dict for look up table
... amortized O(1), with regard to the number of items in the data structure. If you don't need to associate values, use sets.
Memory
Both dictionaries and sets use hashing and they use much more memory than only for object storage. According to A.M. Kuchling in Beautiful Code, the implementation tri...
Correct way to use StringBuilder in SQL
...usually) is to reduce memory churn rather than total memory used, to make life a bit easier on the garbage collector.
Will that take memory equal to using String like below?
No, it'll cause more memory churn than just the straight concat you quoted. (Until/unless the JVM optimizer sees that th...
Checking if a field contains a string
I'm looking for an operator, which allows me to check, if the value of a field contains a certain string.
10 Answers
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How can two strings be concatenated?
...("Hello", "world", sep=" ")
[1] "Hello world"
where the argument sep specifies the character(s) to be used between the arguments to concatenate,
or collapse character vectors
> x <- c("Hello", "World")
> x
[1] "Hello" "World"
> paste(x, collapse="--")
[1] "Hello--World"
where the ar...
is there a require for json in node.js
... There's one gotcha with this. The result will be cached! So if you for some reason need to load the data again (say at a cronjob), you'll get the same old result.
– Juho Vepsäläinen
Nov 18 '13 at 11:21
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How to define a custom ORDER BY order in mySQL
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What if you have a GROUP BY before? For example, the first value i want, appears at the end?
– Pathros
Mar 25 '15 at 18:51
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ng-repeat finish event
...sing directives might be all you need and b) there are a few ng-Repeat specific properties you can use to make your "on ngRepeat finished" event.
Specifically, if all you want is to style/add events to the whole of the table, you can do so using in a directive that encompasses all the ngRepeat elem...
When to create a new app (with startapp) in Django?
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Does that mean, if I make a child model, it must always be in the same app? Since I can't easily drop it into another project without bringing over two "apps"
– Lionel
Feb 10 '11 at 5:22
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error LNK2019: unresolved external symbol _WinMain@16 referenced in function ___tmainCRTStartup
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I had that problem when using MS Visual Studio. If your environment is different that you might have to fix it differently. But it should still be a linker problem.
– Bohdan
Oct 2 '14 at 22:13
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Is it possible to set the stacking order of pseudo-elements below their parent element? [duplicate]
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However, if you have a normal parent div with a background, the lower element will be hidden. In this case, give the parent relative positioning and a z-index of 1. See: jsbin.com/juputice/3/edit
– Stephen Saucie...