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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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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...
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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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How to pass object with NSNotificationCenter

...when you do the addObserver(). The receiveTestNotification should only be called when observing a specific notification. – Johan Karlsson Feb 17 '16 at 15:06 1 ...
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Setting JDK in Eclipse

...f available compilers in the Window -> Preferences -> Java -> Installed JRE's tab. In the project build path configuration dialog, under the libraries tab, you can delete the entry for JRE System Library, click on Add Library and choose the installed JRE to compile with. Some compilers ca...
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No secret option provided to Rack::Session::Cookie warning?

... 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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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 ); } share | imp...
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Is it .yaml or .yml?

...ruling as you can get, but the habit of 8.3 is hard to get out of (and, appallingly, still occasionally relevant in 2013). share | improve this answer | follow ...
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What does template mean?

... template<void (*F)()> struct FunctionWrapper { static void call_it() { F(); } }; // pass address of function do_it as argument. void do_it() { } FunctionWrapper<&do_it> test; Template reference parameter (passing an integer) template<int &A> struct SillyExample { ...
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Understanding PrimeFaces process/update and JSF f:ajax execute/render attributes

...and updating the model values (EditableValueHolder components only) and finally invoke the queued ActionEvent (ActionSource components only). JSF will skip processing of all other components which are not covered by process attribute. Also, components whose rendered attribute evaluates to false duri...