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Use EXCEPT to prevent updates to unchanged records MERGE TargetTable targ USING SourceTable AS src ON src.id = targ.id WHEN MATCHED AND EXISTS ( SELECT src.field EXCEPT SELECT targ.field ) THEN UPDATE SET field = src.field WHEN...

Feather is an implementation of Apache Arrow designed to store data frames in a language agnostic manner while maintaining metadata (e.g. date classes), increasing interoperability between Python and R. Reading a feather file will produce a tibble, not a standard data.frame. library(feather) pat...

The power of AppleScript lies in being able to automate many Mac applications. To find out what you can automate, you need to read an app's scripting dictionary. To do so, launch Script Editor, and select File > Open Dictionary… Once you choose an app, its dictionary will open up in a new win...

Most of the guidance for creating good examples for Q&A carries over into the documentation. Make it minimal and get to the point. Complications and digressions are counterproductive. Include both working code and prose explaining it. Neither one is sufficient on its own. Don't re...

// 1. Base example not using language support for covariance, dynamic type checking. class Top { public: virtual Top* clone() const = 0; virtual ~Top() = default; // Necessary for `delete` via Top*. }; class D : public Top { public: Top* clone() const override ...

// 2. Covariant result version of the base example, static type checking. class Top { public: virtual Top* clone() const = 0; virtual ~Top() = default; // Necessary for `delete` via Top*. }; class D : public Top { public: D* /* ← Covariant return */ clone() const over...

Overrides: Override file: Ext.define('MyApp.override.CornField', override: 'Ext.form.field.Text', initComponent: function () { this.callParent(arguments); this.setValue('Corn!'); } ); Use in app: { xtype: 'textfield' } Extensions: Override file: Ext...

Converts the specified string representation of a date and time to its DateTime equivalent using the specified format, culture-specific format information, and style. The format of the string representation must match the specified format exactly. The method returns a value that indicates whether th...

Convert the argument to hexadecimal. This is used for strings. HEX('fööbar') -- 66F6F6626172 -- in "CHARACTER SET latin1" because "F6" is hex for ö HEX('fööbar') -- 66C3B6C3B6626172 -- in "CHARACTER SET utf8 or utf8mb4" because "C3B6" is hex for ö

const source = Rx.Observable.range(1, 3) .map((x, idx, obs) => `Element ${x} was at position ${idx}`); const subscription = source.subscribe( x => console.log(`Next: ${x}`), err => console.log(`Error: ${err}`), () => console.log(`Completed`) ); // => Next: Element 1...

Often when building a Docker image, the Dockerfile contains instructions that runs programs to fetch resources from the Internet (wget for example to pull a program binary build on GitHub for example). It is possible to instruct Docker to pass set set environment variables so that such programs per...

textOnCurve(text,offset,x1,y1,x2,y2,x3,y3,x4,y4) Renders text on quadratic and cubic curves. text is the text to render offset distance from start of curve to text >= 0 x1,y1 - x3,y3 points of quadratic curve or x1,y1 - x4,y4 points of cubic curve or Example usage: textOnCurve("...

You can create extension methods to improve usability for nested collections like a Dictionary with a List<T> value. Consider the following extension methods: public static class DictListExtensions { public static void Add<TKey, TValue, TCollection>(this Dictionary<TKey, TColl...

You can concatenate strings separated by delimiter using the string_agg() function. If your individuals table is: NameAgeCountryAllie15USAAmanda14USAAlana20Russia You could write SELECT ... GROUP BY statement to get names from each country: SELECT string_agg(name, ', ') AS names, country FROM ...

Bash can easily create lists from alphanumeric characters. # list from a to z $ echo {a..z} a b c d e f g h i j k l m n o p q r s t u v w x y z # reverse from z to a $ echo {z..a} z y x w v u t s r q p o n m l k j i h g f e d c b a # digits $ echo {1..20} 1 2 3 4 5 6 7 8 9 10 11...

After launching Visual Studio 2015, go to File → New → Project. In the New Project dialog box, browse in the templates tree to Visual C# → Windows → Universal and select Blank App (Universal Windows). Next, we need to fill the form to describe the Application: Name: this is the name of the appli...

You might want to import and export your database for bacukups for example. Dont forget about the permissions. public void exportDatabase(){ try { File sd = Environment.getExternalStorageDirectory(); File data = Environment.getDataDirectory(); String currentD...

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Most printable characters can be included in string or regular expression literals just as they are, e.g. var str = "ポケモン"; // a valid string var regExp = /[Α-Ωα-ω]/; // matches any Greek letter without diacritics In order to add arbitrary characters to a string or regular expression,...

This is a basic project that uses FXML, created with NetBeans (New Project -> JavaFX -> JavaFX FXML Application). It contains just three files: Main Application class package org.stackoverflow; import javafx.application.Application; import javafx.fxml.FXMLLoader; import javafx.scene.Par...