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Common table expressions support extracting portions of larger queries. For example: WITH sales AS ( SELECT orders.ordered_at, orders.user_id, SUM(orders.amount) AS total FROM orders GROUP BY orders.ordered_at, orders.user_id ) SELECT sales.ordered_at, sales.total,...

This example generates random values between 0 and 2147483647. Random rnd = new Random(); int randomNumber = rnd.Next();

Generate a random number between 0 and 1.0. (not including 1.0) Random rnd = new Random(); var randomDouble = rnd.NextDouble();

Generate a random number between minValue and maxValue - 1. Random rnd = new Random(); var randomBetween10And20 = rnd.Next(10, 20);

When creating Random instances with the same seed, the same numbers will be generated. int seed = 5; for (int i = 0; i < 2; i++) { Console.WriteLine("Random instance " + i); Random rnd = new Random(seed); for (int j = 0; j < 5; j++) { Console.Write(rnd.Next(...

Two Random class created at the same time will have the same seed value. Using System.Guid.NewGuid().GetHashCode() can get a different seed even in the same time. Random rnd1 = new Random(); Random rnd2 = new Random(); Console.WriteLine("First 5 random number in rnd1"); for (int i = 0...

The main methods that are useful with this class are popleft and appendleft from collections import deque d = deque([1, 2, 3]) p = d.popleft() # p = 1, d = deque([2, 3]) d.appendleft(5) # d = deque([5, 2, 3])

Average The AVG() aggregate function will return the average of values selected. SELECT AVG(Salary) FROM Employees Aggregate functions can also be combined with the where clause. SELECT AVG(Salary) FROM Employees where DepartmentId = 1 Aggregate functions can also be combined with group by ...

There are three visibility types that you can apply to methods (class/object functions) and properties (class/object variables) within a class, which provide access control for the method or property to which they are applied. You can read extensively about these in the PHP Documentation for OOP Vi...

Include a row number according to the order specified. SELECT ROW_NUMBER() OVER(ORDER BY Fname ASC) AS RowNumber, Fname, LName FROM Employees

Uses a partition criteria to group the row numbering according to it. SELECT ROW_NUMBER() OVER(PARTITION BY DepartmentId ORDER BY DepartmentId ASC) AS RowNumber, DepartmentId, Fname, LName FROM Employees

This query selects all employees not on the Supervisors table. SELECT * FROM Employees WHERE EmployeeID not in (SELECT EmployeeID FROM Supervisors) The same results can be achieved using a LEFT JOIN. SELECT * FROM Employees AS e LEFT JOIN Supervisors AS s ON s.E...

Definition : When multiple methods with the same name are declared with different parameters, it is referred to as method overloading. Method overloading typically represents functions that are identical in their purpose but are written to accept different data types as their parameters. Factors af...

Jasmine can spy on an existing function using the spyOn function. let calculator = { multiply: function(a, b) { return a * b; }, square: function(a) { return this.multiply(a, a); } } describe('calculator', function() { it('squares numbers by multiplying them by the...

We can use jasmine.createSpy() to create a standalone spy. This is often useful if we need to pass a function as a callback to another function and want to test how it is used. // source code function each(arr, fn) { arr.forEach(fn); } // test code describe('each', function() { let m...

The NSDate class provides methods for creating NSDate objects corresponding to a given date and time. An NSDate can be initialized using the designated initializer, which: Returns an NSDate object initialized relative to 00:00:00 UTC on 1 January 2001 by a given number of seconds. NSDate *date...

We can match on lists like any other data type, though they are somewhat unique, in that the constructor for building up lists is the infix function ::. (See the example Creating a list for more on how that works.) matchMyList : List SomeType -> SomeOtherType matchMyList myList = case myL...

Moment is a javascript library that was designed to make working with dates and times less time-consuming and more intuitive. You can easily start using this library by installing it in you web-app by using one of the following guides. Browser You can either download the JS file from the official...

If you're ever dealing with C Binary API's from Perl Code, via the syscall, ioctl, or fcntl functions, you need to know how to construct memory in a C Compatible way. For instance, if you were ever dealing with some function that expected a timespec, you'd look into /usr/include/time.h and find: s...