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How many database indexes is too many?
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I voted up but... I would say the extra parse time while interesting and academic, it would never influence my choice for the correct number of indexes. agree?
– Stephanie Page
May 30 '13 at 21:14
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What is this date format? 2011-08-12T20:17:46.384Z
...nd the Z means "zero hour offset" also known as "Zulu time" (UTC). If your strings always have a "Z" you can use:
SimpleDateFormat format = new SimpleDateFormat(
"yyyy-MM-dd'T'HH:mm:ss.SSS'Z'", Locale.US);
format.setTimeZone(TimeZone.getTimeZone("UTC"));
Or using Joda Time, you can use ISODat...
Want to find records with no associated records in Rails
...ager loading table(s) Currently, Active Record recognizes the table in the string, and knows to JOIN the comments table to the query, rather than loading comments in a separate query. However, doing this without writing a full-blown SQL parser is inherently flawed. Since we don't want to write an SQ...
Hash function that produces short hashes?
Is there a way of encryption that can take a string of any length and produce a sub-10-character hash? I want to produce reasonably unique ID's but based on message contents, rather than randomly.
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Does JavaScript guarantee object property order?
...imply put, the iteration order is a combination of the insertion order for strings keys, and ascending order for number-like keys:
// key order: 1, foo, bar
const obj = { "foo": "foo", "1": "1", "bar": "bar" }
Using an array or a Map object can be a better way to achieve this. Map shares some simil...
html (+css): denoting a preferred place for a line break
...oblems if the text you're breaking is copied and parsed somehow - then the extra digit might be in the way. If you try to break an email at the @, copy and paste would fail with no clue to the user why not. If you expect the data to be read by crawlers or copy pasted, I wouldn't advice this solution...
What is the difference between dict.items() and dict.iteritems() in Python2?
...eal list of tuples and returned that. That could potentially take a lot of extra memory.
Then, generators were introduced to the language in general, and that method was reimplemented as an iterator-generator method named iteritems(). The original remains for backwards compatibility.
One of Pyth...
Why do we need tuples in Python (or any immutable data type)?
...mutable objects can allow substantial optimization; this is presumably why strings are also immutable in Java, developed quite separately but about the same time as Python, and just about everything is immutable in truly-functional languages.
in Python in particular, only immutables can be hashable ...
Resizing an iframe based on content
...frame(height);
}
// Helper function, parse param from request string
function getParam( name )
{
name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");
var regexS = "[\\?&]"+name+"=([^&#]*)";
var regex = new RegExp( regexS );
var r...
How to create a video from images with FFmpeg?
...estions/587511/concatenate-multiple-wav-files-using-single-command-without-extra-file
Tested on
ffmpeg 3.4.4, vlc 3.0.3, Ubuntu 18.04.
Bibliography
http://trac.ffmpeg.org/wiki/Slideshow official wiki
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