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A computed column is computed from an expression that can use other columns in the same table. The expression can be a noncomputed column name, constant, function, and any combination of these connected by one or more operators. Create table with a computed column Create table NetProfit ( Sa...

There are a few ways to inspect the contents of a zipfile. You can use the printdir to just get a variety of information sent to stdout with zipfile.ZipFile(filename) as zip: zip.printdir() # Out: # File Name Modified Size ...

Multiple comparison operators used together are chained, as if connected via the && operator. This can be useful for readable and mathematically concise comparison chains, such as # same as 0 < i && i <= length(A) isinbounds(A, i) = 0 < i ≤ length(A) # same as Set...

Sometimes, one wants to run some initialization code once before testing a condition. In certain other languages, this kind of loop has special do-while syntax. However, this syntax can be replaced with a regular while loop and break statement, so Julia does not have specialized do-while syntax. Ins...

A lot of people who are new to multi-threading think that using threads automatically make an application go faster. In fact, it is a lot more complicated than that. But one thing that we can state with certainty is that for any computer there is a limit on the number of threads that can be run at ...

When programming in Prolog it is not always possible, or desirable, to create predicates which unify for every possible combination of parameters. For example, the predicate between(X,Y,Z) which expresses that Z is numerically between X and Y. It is easily implemented in the cases where X, Y, and Z ...

Immediately continue reading on invalid input or break on user request or end-of-file: #include <stdlib.h> /* for EXIT_xxx macros */ #include <stdio.h> /* for printf() and getchar() */ #include <ctype.h> /* for isdigit() */ void flush_input_stream(FILE * fp); int main(v...

In Gloss, one can use the display function to create very simple static graphics. To use this one needs to first import Graphics.Gloss. Then in the code there should the following: main :: IO () main = display window background drawing window is of type Display which can be constructed in two ...

Increase the saturation level of an image with ctx.globalCompositeOperation = 'saturation'; The amount of the effect can be controled with the alpha setting or the amount of saturation in the fill overlay // Render the image ctx.globalCompositeOperation='source-atop'; ctx.drawImage(image, 0, ...

Detailed instructions on getting wordpress-theming set up or installed. Wordpress is opensource.You can find large set of theme for use free or premium themes.All theme are provide a documentation for install and use. What you have to understand while choose a theme? Wordpress version you are ...

Excel formulas are used to process simple or complex equations and output the result to a specific cell within a worksheet. (There is an exception to this where the WorksheetFunction class is used in VBA programming, however VBA is out of scope for this tag - please refer to the excel-vba or vba ...

This function return the standart gravity constant in the specified acceleration units (1 for cm/s², 2 for ft/s², 3 for m/s²) /** * Returns the standard gravity constant in the specified acceleration units * Values taken from https://en.wikipedia.org/wiki/Standard_gravity on July 24, 2016. ...

Html5 Canvas gives you the ability to fetch and change the color of any pixel on the canvas. You can use Canvas's pixel manipulation to: Create a color-picker for an image or select a color on a color-wheel. Create complex image filters like blurring and edge detection. Recolor any part of an ...

PrepareForSegue: func prepareForSegue(_ segue:UIStoryboardSegue, sender sender:AnyObject?) Notifies the view controller that a segue is about to be performed Parameters segue: The segue object. sender: The object that initialized the segue. Example in Swift Perform a task if the ident...

Unwind Segues Unwind Segues give you a way to “unwind” the navigation stack and specify a destination to go back to. The signature of this function is key to Interface Builder recognizing it. It must have a return value of IBAction and take one parameter of UIStoryboardSegue. The name of the ...

Description: phpMyAdmin is a free software tool written in PHP, intended to handle the administration of MySQL over the Web. phpMyAdmin supports a wide range of operations on MySQL and MariaDB. Frequently used operations (managing databases, tables, columns, relations, indexes, users, permissions, ...

Map k v provides a Monoid instance with the following semantics: mempty is the empty Map, i.e. the same as Map.empty m1 <> m2 is the left-biased union of m1 and m2, i.e. if any key is present both in m1 and m2, then the value from m1 is picked for m1 <> m2. This operation is also ava...

You can use the heroku create command to create a Heroku application. Each application you deploy to Heroku has its own code base, environment variables, addons, etc. Each Heroku application has a globally unique name. If you try to create a Heroku application whose name is already taken, you will ...

This example demonstrates usage of lockf function (POSIX XSI). Notes: Only exclusive locks are supported. Can be applied to a byte range, optionally automatically expanding when data is appended in future (controlled by len argument and position set with lseek function). Locks are released on ...

Components and Props As React concerns itself only with an application's view, the bulk of development in React will be the creation of components. A component represents a portion of the view of your application. "Props" are simply the attributes used on a JSX node (e.g. <SomeComponen...