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In Firebase, is there a way to get the number of children of a node without loading all the node dat

... The code snippet you gave does indeed load the entire set of data and then counts it client-side, which can be very slow for large amounts of data. Firebase doesn't currently have a way to count children without loading data, but we do plan to add it. For now, one solution would be to mai...
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Heroku deployment error H10 (App crashed)

...on heroku were not revealing any clues. I read other answers on this page and broke out in a sweat after seeing "rebuilding the app." I figured maybe I could get in the heroku console and look around. I did and even the console crashed, but this time it told me why. It was some obscure variable ...
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How to tell if a JavaScript function is defined

... And yes, "magic" was a sloppy, poor word choice - I meant "literal string" not "magic string." My bad. :) – Jason Bunting Nov 24 '10 at 22:35 ...
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Add border-bottom to table row

...e of 3 by 3. I need a way to add a border for the bottom of every row tr and give it a specific color. 16 Answers ...
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How to make clang compile to llvm IR

... to LLVM bytecode rather than binary executable. How can I achieve that? And if I get the LLVM bytecode, how can I take it to further compile it to binary executable. ...
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How to apply a function to two columns of Pandas dataframe

Suppose I have a df which has columns of 'ID', 'col_1', 'col_2' . And I define a function : 12 Answers ...
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Vertically aligning CSS :before and :after content [duplicate]

... the question was about vertically aligning :before and :after elements and thats what the fiddles do, also in your screenshot – fassl Aug 26 '16 at 7:04 ...
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typeof !== “undefined” vs. != null

...n the two. In many cases, == can be better, because it tests for both null and undefined. – seanmonstar Jun 19 '12 at 16:58 10 ...
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What is the difference between gsub and sub methods for Ruby Strings

I have been perusing the documentation for String today, and I saw the :sub method, which I'd never noticed before. I've been using :gsub and it appears that they are essentially the same. Can anyone explain the difference to me? Thanks! ...
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What is the difference between async.waterfall and async.series

...s://github.com/caolan/async provides 2 similar methods, async.waterfall and async.series . 4 Answers ...