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Why are dates calculated from January 1st, 1970?

...1st, 1970) as default standard The Question makes two false assumptions: All time-tracking in computing is done as a count-since-1970. Such tracking is standard. Two Dozen Epochs Time in computing is not always tracked from the beginning of 1970 UTC. While that epoch reference is popular, various...
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When to encode space to plus (+) or %20?

...value is query value with a space, but the folder name in the path is literally foo+bar, not foo bar. %20 is a valid way to encode a space in either of these contexts. So if you need to URL-encode a string for inclusion in part of a URL, it is always safe to replace spaces with %20 and pluses with ...
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MySQL: Fastest way to count number of rows

...olumn indexes, so it will be the best result. Mysql with MyISAM engine actually stores row count, it doensn't count all rows each time you try to count all rows. (based on primary key's column) Using PHP to count rows is not very smart, because you have to send data from mysql to php. Why do it whe...
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Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=

...: SET @rUsername = ‘aname’ COLLATE utf8_unicode_ci; -- COLLATE added CALL updateProductUsers(@rUsername, @rProductID, @rPerm); Option 2: add COLLATE to the WHERE clause: CREATE PROCEDURE updateProductUsers( IN rUsername VARCHAR(24), IN rProductID INT UNSIGNED, IN rPerm VARCHAR(16...
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Get the first element of an array

... a array "copy" is needed: array_shift(array_slice($array, 0, 1)); With PHP 5.4+ (but might cause an index error if empty): array_values($array)[0]; share | improve this answer | ...
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Perform .join on value in array of objects

...Array.prototype.map is what you're looking for if you want to code functionally. [ {name: "Joe", age: 22}, {name: "Kevin", age: 24}, {name: "Peter", age: 21} ].map(function(elem){ return elem.name; }).join(","); In modern JavaScript: [ {name: "Joe", age: 22}, {name: "Kevin", age: 2...
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What is the difference between statically typed and dynamically typed languages?

I hear a lot that new programming languages are dynamically typed but what does it actually mean when we say a language is dynamically typed vs. statically typed? ...
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Nginx no-www to www and www to no-www

...n.php last; # etc etc... } } Note: I have not originally included https:// in my solution since we use loadbalancers and our https:// server is a high-traffic SSL payment server: we do not mix https:// and http://. To check the nginx version, use nginx -v. Strip www from ...
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counting number of directories in a specific directory

... can instead test the directory's children and do not descend into them at all: $ find .vim/* -maxdepth 0 -type d .vim/after .vim/autoload .vim/bundle .vim/colors .vim/compiler .vim/doc .vim/ftdetect .vim/ftplugin .vim/indent .vim/plugin .vim/syntax $ find .vim/* -maxdepth 0 -type d | wc -l 11 $ f...
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ng-app vs. data-ng-app, what is the difference?

... It seems like such a waste of CPU cycles to manually strip off data- and x-. Why can't the HTML validation rules be changed to accept ng- stuff? – DaveAlger May 13 '15 at 14:43 ...