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SET versus SELECT when assigning variables?
...ed then SET will assign NULL, where SELECT will not make the assignment at all (so the variable will not be changed from its previous value)
As far as speed differences - there are no direct differences between SET and SELECT. However SELECT's ability to make multiple assignments in one shot does ...
Check synchronously if file/directory exists in Node.js
... Note that fs.exists() is deprecated, but fs.existsSync() is not. (The
callback parameter to fs.exists() accepts parameters that are
inconsistent with other Node.js callbacks. fs.existsSync() does not
use a callback.)
You've specifically asked for a synchronous check, but if you can use an ...
Real World Use of Zookeeper [closed]
...wondered whether anybody was using it currently and what they were specifically using it for storing.
13 Answers
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How to filter specific apps for ACTION_SEND intent (and set a different text for each app)
...tion in various ways, but nobody has answered it completely yet.
My spec called for the user to be able to choose email, twitter, facebook, or SMS, with custom text for each one. Here is how I accomplished that:
public void onShareClick(View v) {
Resources resources = getResources();
Inte...
Map vs Object in JavaScript
...stored at a key. Because of this, Objects have been used as Maps
historically; however, there are important differences between Objects
and Maps that make using a Map better.
An Object has a prototype, so there are default keys in the map.
However, this can be bypassed using map = Object....
Rollback to an old Git commit in a public repo
...hould be good.
You can undo this by
git reset --hard
that will delete all modifications from the working directory and staging area.
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“CAUTION: provisional headers are shown” in Chrome debugger
...ield to find the event related to your resource (use parts of the URL).
Finally, click on the event and see if the info shown tells you something.
For Older Versions of chrome
Type chrome://net-internals in the address bar and hit enter.
Open the page that is showing problems.
Go back to net-int...
How can I pad a value with leading zeros?
... If performance is a concern for you, don't use this solution!
Potentially outdated: ECMAScript 2017 includes String.prototype.padStart and Number.prototype.toLocaleString is there since ECMAScript 3.1. Example:
var n=-0.1;
n.toLocaleString('en', {minimumIntegerDigits:4,minimumFractionDigits:2...
Why would one omit the close tag?
...e file (and possibly some other factors I don't want to bore you with).
Finally, many PHP frameworks including Symfony, Zend and Laravel (there is no mention of this in the coding guidelines but it follows the suit) and the PSR-2 standard (item 2.2) require omission of the closing tag. PHP manual it...
Linux日志管理Rsyslog入门 - C/C++ - 清泛网移动版 - 专注C/C++及内核技术
...g，其配置大致如下所示：
shell> cat /etc/syslog.conf
# Log all kernel messages to the console.
# Logging much else clutters up the screen.
# kern.* /dev/console
# Log anything (except mail) of level info or higher.
# Don't log private authentication messages!
*.info;mail.none;...