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MySQL CONCAT returns NULL if any field contain NULL
...es: it returns the first non-NULL value parameter passed to it (or NULL if all parameters are NULL). By passing an empty string as the second parameter, you are guaranteeing it will not return NULL.
– Jo.
Mar 10 '17 at 17:03
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How can I remove a key and its value from an associative array?
...oop, then you need to prepend an ampersand to your enumeration variable to allow write access.
– FreeAsInBeer
Jul 30 '12 at 21:20
1
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Get the current displaying UIViewController on the screen in AppDelegate.m
...d can be easily reused.
So I created a category on UIWindow. You can now call visibleViewController on UIWindow and this will get you the visible view controller by searching down the controller hierarchy. This works if you are using navigation and/or tab bar controller. If you have another type of...
How to start working with GTest and CMake
...that I just tested. It downloads directly from the web, either a fixed tarball, or the latest subversion directory.
cmake_minimum_required (VERSION 3.1)
project (registerer)
##################################
# Download and install GoogleTest
include(ExternalProject)
ExternalProject_Add(gtest
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What is the difference between ELF files and bin files?
...ded loader format ELf file ,what is the difference between the two , especially the utility of ELF file.
4 Answers
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What are the mathematical/computational principles behind this game?
My kids have this fun game called Spot It! The game constraints (as best I can describe) are:
9 Answers
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No secret option provided to Rack::Session::Cookie warning?
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Update your rails gems as this is backported to all supported rails gems. note @henrik-n
– shadowbq
Feb 4 '13 at 11:14
add a comment
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What is the motivation for bringing Symbols to ES6?
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Most languages (all mainstream ones afaik) provide some mechanism, usually reflection, to get access to private anyway.
– Esailija
May 14 '14 at 10:58
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Clear form field after select for jQuery UI Autocomplete
...it works around line 109 here.
The code in there checks for false specifically:
if ( false !== self._trigger( "select", event, { item: item } ) ) {
self.element.val( item.value );
}
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imp...
When to Redis? When to MongoDB? [closed]
... and MongoDB. I know they are different; the performance and the API is totally different.
10 Answers
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