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How do I check if a column is empty or null in MySQL?
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This will select all rows where some_col is NULL or '' (empty string)
SELECT * FROM table WHERE some_col IS NULL OR some_col = '';
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Converting many 'if else' statements to a cleaner approach [duplicate]
...ng this approach you could easily add different converters in the future.
All untested, probably doesn't compile, but you get the idea
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Angular IE Caching issue for $http
All the ajax calls that are sent from the IE are cached by Angular and I get a 304 response for all the subsequent calls. Although the request is the same, the response is not going be the same in my case. I want to disable this cache. I tried adding the cache attribute to $http.get but still it...
How to place the ~/.composer/vendor/bin directory in your PATH?
I'm on Ubuntu 14.04 and I've been trying all possible methods to install Laravel to no avail. Error messages everything I try. I'm now trying the first method in the quickstart documentation, that is, via Laravel Installer, but it says to "Make sure to place the ~/.composer/vendor/bin directory in...
Is it expensive to use try-catch blocks even if an exception is never thrown?
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try has almost no expense at all. Instead of doing the work of setting up the try at runtime, the code's metadata is structured at compile time such that when an exception is thrown, it now does a relatively expensive operation of walking up the stack an...
Convert String to Type in C# [duplicate]
...he type (with its namespace, of course) if the type is in mscorlib or the calling assembly. Otherwise, you've got to include the assembly name as well:
Type type = Type.GetType("Namespace.MyClass, MyAssembly");
If the assembly is strongly named, you've got to include all that information too. See...
When to wrap quotes around a shell variable?
... quote it if it can either be empty or contain spaces (or any whitespace really) or special characters (wildcards). Not quoting strings with spaces often leads to the shell breaking apart a single argument into many.
$? doesn't need quotes since it's a numeric value. Whether $URL needs it depends o...
mingw-w64 threads: posix vs win32
I'm installing mingw-w64 on Windows and there are two options: win32 threads and posix threads. I know what is the difference between win32 threads and pthreads but I don't understand what is the difference between these two options. I doubt that if I will choose posix threads it will prevent me fro...
What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
... NULL is less efficient
In PostgreSQL, NOT IN is less efficient
In Oracle, all three methods are the same.
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Chrome DevTools Devices does not detect device when plugged in
...s://developers.google.com/chrome-developer-tools/docs/remote-debugging
Install Windows USB driver http://developer.samsung.com/android/tools-sdks/Samsung-Android-USB-Driver-for-Windows
Install Android SDK http://developer.android.com/sdk/index.html
Install Android SDK Platform-tools http://developer...