ECMAScript 6 (ES6) is the specification or standard followed by many programming languages like JavaScript, JScript, ActionScript, etc. The most popular programmimg language following this specification is JavaScript, That is why many people call ECMAScript 6 JavaScript 6 New features introduced in ECMAScript 6: The let statement allows you to declare a variable with block […]
Angular is a front-end framework brought by Google based on TypeScript To write apps with Angular you have to first install Angular CLI which will set up a Angular project for you Install Angular CLI using NPM: C:\>npm install -g @angular/cli -g stands for global Create a new Angular project called helloworld with Angular CLI […]
Open up Developer Tools in Chrome and Firefox Windows: Ctrl + Shift + I Mac: Cmd + Option + I Open up the JavaScript Console Windows: Ctrl + Shift + J Mac: Cmd + Option + J View Page Source Code: Windows: Ctrl + U Mac: Cmd + U Multi-Cursor Editing (Using Multiple Cursors) Select […]
Node.js is a Runtime Enviroment for executing JavaScript code outside the browser Node.js is Asynchronous by default. Which means Node.js can handel several requests at the same time When naming classes in Node.js the first letter of every word in the class name should be uppercase e.g. EventEmmitter. This convention is called Pascal Case (PascalCase) […]
Assuming you have these two MySQL tables
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customers +--+------------------+-------------------+ |id|name |address | +--+------------------+-------------------+ | 1| Leanne Graham |4208 Shobe Lane | | 2| Janet Pruett |1462 Hamilton Drive| +--+------------------+-------------------+ credit-cards +--+------------+------------+ |id|costumers_id| expiry_date| +--+------------+------------+ | 1| 1| 2009-11-17| | 2| 2| 2030-12-31| +--+------------+------------+ |
You can ask MySQL to show you all customers who has a valid credit card
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SELECT c.id, c.name, c.address, cc.expiry_date FROM customers AS c LEFT JOIN credit-cards AS cc ON c.id = cc.parent_id WHERE cc.expiry_date > now() |
MySQL output
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+----+------------+-------------------+--------------+ |c.id|c.name |c.address |cc.expiry_date| +----+------------+----------------------------------+ | 1|Janet Pruett|1462 Hamilton Drive| 2030-12-31| +----+------------+-------------------+--------------+ |
MySQL is a relational database that uses the SQL language. SQL stands for Structured Query Language, e.g.:
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SELECT last_name, first_name, street, street_nummber, postal_code, city FROM costumers |
