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SQL JOIN vs IN performance?
...d out which one works better, you'd need to actually profile the execution times.
As a general rule of thumb, I think if you have indices on your foreign key columns, and if you're using only (or mostly) INNER JOIN conditions, then the JOIN will be slightly faster.
But as soon as you start using O...
Is it possible only to declare a variable without assigning any value in Python?
...e I have with this was I was keeping track of a counter (minValue) and any time a value was lower than it, I was setting it to become the new minValue. If I declared minValue as None originally, then apparently it is still lower than any numbers I compared it against. I ended up just initializing it...
How to check if a string contains text from an array of substrings in JavaScript?
...ple lines and know whether your array was 1 or zero based, yeah...half the time you got it wrong and had to debug and look out for a little bugger called 'i'.
– aamarks
Apr 21 '18 at 0:15
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(this == null) in C#!
...ehaving correctly according to the spec (even in Beta 1, this is a compile time error):
§ 7.5.7 This access
A this-access consists of the reserved word this.
this-access:
this
A this-access is permitted only in the block of an instance constructor, an instance method, or an ins...
Convert absolute path into relative path given a current directory using Bash
...t for /usr/bin/nmap: from nmap to /tmp/testing it is only ../../ and not 3 times ../. It works however, because doing .. on the rootfs is /.
– Patrick B.
Mar 6 '18 at 14:50
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CSS to stop text wrapping under image
...asically the region occupied by an element with a block-type flow.
Every time it is applied, overflow: hidden creates a new block formatting context. But it's not the only property capable of triggering that behaviour. Quoting a presentation by Fiona Chan from Sydney Web Apps Group:
float: ...
How to get multiple counts with one SQL query?
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@MajidLaissi yes it did, changed my query time from a minute to less than a second. :)
– Abner
Apr 7 at 3:39
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How do I create my own URL protocol? (e.g. so://…) [closed]
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This is from .Net 2.0 runtime (note, this included 3.0 and 3.5) timeframe. It didn't support different CLR runtimes in the same process, so if I wrote a 1.0 handler and you wrote a 2.0 one, and both of our products were installed on a customers compu...
Different between parseInt() and valueOf() in java?
How is parseInt() different from valueOf() ?
11 Answers
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Change the color of a bullet in a html list?
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@KoenHoutman, at the time this was written (2008) it was the only technique with reasonable support. Even today it is not a bad practice and still is the technique with the broadest browser support, although I agree that today (in most cases) I w...