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The following example can be used to find the total row count for a specific table in a database if table_name is replaced by the the table you wish to query: SELECT COUNT(*) AS [TotalRowCount] FROM table_name; It is also possible to get the row count for all tables by joining back to the table'...

This is something that can be frustrating: you make a visualisation using D3.js but the rectangle you want on top is hidden behind another rectangle, or the line you planned to be behind some circle is actually over it. You try to solve this using the z-index in your CSS, but it doesn't work (in SVG...

First of all, ensure that you've enabled the 'Virtualization' in your BIOS setup. Start the Android SDK Manager, select Extras and then select Intel Hardware Accelerated Execution Manager and wait until your download completes. If it still doesn't work, open your SDK folder and run /extras/intel/Ha...

First define an ExitActivity in the AndroidManifest.xml <activity android:name="com.your_example_app.activities.ExitActivity" android:autoRemoveFromRecents="true" android:theme="@android:style/Theme.NoDisplay" /> Afterwards the ExitA...

/** * Created by Nick Cardoso on 03/08/16. * This is not a complete parcelable implementation, it only highlights the easiest * way to read and write your Enum values to your parcel */ public class Foo implements Parcelable { private final MyEnum myEnumVariable; private final M...

To determine the version of Azure PowerShell that you have installed, run the following: Get-Module -ListAvailable -Name Azure -Refresh This command returns the installed version even when you haven't loaded the Azure PowerShell module in your current PowerShell session.

Step 1. In your host machine (Windows/Linux/OSX), create an empty dir my_project. Step 2. Create a file named Vagrantfile with this: Vagrant.configure("2") do |config| config.vm.box = "gbarbieru/xenial" #An Ubuntu 16.04 based image config.vm.hostname = "my_project&...

The first mistake that nearly every single programmer makes is presuming that this code will work as intended: float total = 0; for(float a = 0; a != 2; a += 0.01f) { total += a; } The novice programmer assumes that this will sum up every single number in the range 0, 0.01, 0.02, 0.03, .....

Not all type erasure involves virtual inheritance, allocations, placement new, or even function pointers. What makes type erasure type erasure is that it describes a (set of) behavior(s), and takes any type that supports that behavior and wraps it up. All information that isn't in that set of beha...

The n & (n - 1) trick (see Remove rightmost set bit) is also useful to determine if an integer is a power of 2: bool power_of_2 = n && !(n & (n - 1)); Note that without the first part of the check (n &&), 0 is incorrectly considered a power of 2.

Install Iron Router From the terminal: meteor add iron:router Basic configuration Router.configure({ //Any template in your routes will render to the {{> yield}} you put inside your layout template layoutTemplate: 'layout', loadingTemplate: 'loading' }); Render without d...

Simple pattern for filtering subscriptions on the server, using regexes, reactive session variables, and deps autoruns. // create our collection WordList = new Meteor.Collection("wordlist"); // and a default session variable to hold the value we're searching for Session.setDefault('...

If the Node event loop acts like a bicycle chain, the server-side collection observer is like a derailleur. It's a gearing mechanism that is going to sit on the data collection as the data comes in. It can be very performant, as all race bicycles have derailleurs. But it's also a source for breaking...

Inspecting an Object You can find the public methods an object can respond to using either the methods or public_methods methods, which return an array of symbols: class Foo def bar; 42; end end f = Foo.new def f.yay; 17; end p f.methods.sort #=> [:!, :!=, :!~, :<=>, :==, :===, :=...

It is possible to query an object about its instance variables using instance_variables, instance_variable_defined?, and instance_variable_get, and modify them using instance_variable_set and remove_instance_variable: class Foo attr_reader :bar def initialize @bar = 42 end end f = F...

The Kernel exposes methods for getting the list of global_variables and local_variables: cats = 42 $demo = "in progress" p global_variables.sort #=> [:$!, :$", :$$, :$&, :$', :$*, :$+, :$,, :$-0, :$-F, :$-I, :$-K, :$-W, :$-a, #=> :$-d, :$-i, :$-l, :$-p, :$-v, :$-w, :$...

Classes and modules have the same methods for introspecting instance variables as any other object. Class and modules also have similar methods for querying the class variables (@@these_things): p Module.methods.grep(/class_variable/) #=> [:class_variables, :class_variable_get, :remove_class_va...

pie view - (void)drawRect:(CGRect)rect { NSArray *data = @[@30, @15, @5, @17, @3, @10, @20]; // 1. context CGContextRef cxtRef = UIGraphicsGetCurrentContext(); CGPoint center = CGPointMake(150, 150); CGFloat radius = 150; __block CGFloat startAngle = 0; ...

Some websites don’t like to be scraped. In these cases you may need to simulate a real user working with a browser. Selenium launches and controls a web browser. from selenium import webdriver browser = webdriver.Firefox() # launch firefox browser browser.get('http://stackoverflow.com/questi...

/* PL/SQL is a core Oracle Database technology, allowing you to build clean, secure, optimized APIs to SQL and business logic. */ set serveroutput on BEGIN DBMS_OUTPUT.PUT_LINE ('Hello World!'); END;