Recent Articles Changed

What is URL encoding ? known also as Percent-encoding

Modified Jun 24 - 10:17

URL In a URL / Uniform Resource Identifier (URI), you have reserved character that are part of the URL syntax that cannot be used. For instance: the scheme separator : or the path separator / Percent-encoding, also known as Url Encoding maps (ie "...

Language - Object

Modified Jun 23 - 18:15

Objects are values that hold other values at specific named locations called properties (Property in this context may be a method or a variable) An object can be seen as a single data structure that contains: data as well as functions; functions of "...

Java - (Inheritance|Class Hierarchy) - (Subclass|Superclass) - (Extends, Super) - ( is a relationship)

Modified Jun 23 - 14:41

“” See . The Java programming language does not permit multiple inheritance, but interfaces provide an alternative. Keyword Extends The syntax for creating a subclass is simple. At the beginning of your class declaration, use the supeconstructor "...

Css - Declaration

Modified Jun 23 - 09:14

Declaration are syntactic expressions that are contained in a declaration block to create a rule A declaration: is either empty or has two parts (separated by a colon (:) and optionally surrounded by space): A property name, A property value. Be "...

SVG - View Box

Modified Jun 21 - 14:26

The Viewbox attribute specifies: a boundary box in which only the inside elements are visible. and how to resize / fit its content when the viewport is changing. SVG viewport Syntax The viewBox specify a rectangle in user space which should be map "...


Modified Jun 21 - 07:15

A color is: a light wave in a range called the visual spectrum (that our eye see) the absence of light or mixed (achromatic colors (white, black, gray) in computer a data type that denotes a color. A color can be called by its name (or the color n "...

What are the colors emotions ? (meaning / symbolism)

Modified Jun 21 - 07:13

Color emotion (known also as color psychology) is based on the human feeling that a color evokes.

Recent Articles Created

What is a trait in Php ?

Created Jun 23 - 14:50

A trait is a collection of code that is added dynamically to your class. It helps to alleviate the limitation of class hierarchy (object inheritance) when: objects should share method that can't be applied to all objects (through hierarchy / inheri...

How to represent an image in HTML ?

Created Jun 18 - 09:45

HTML An image in HTML can be represented by: the img element (from raster to svg image) the svg element the picture element imgpictureresponsive image

Git - rev-parse

Created Jun 03 - 11:35

rev-parse is a command line tool that permits to parse the output and output a single value. Example For a commit to print the commit tree hash

Git - Database

Created Jun 03 - 09:46

The git core database is a key store value where a key value entry is known as an object. Tree The database is mostly composed: of tree ... and commit

What are short status ?

Created Jun 03 - 09:16

short status is a one letter that summarize the file status List Added (A), Copied (C), Deleted (D), Modified (M), Renamed (R), have their type (i.e. regular file, symlink, submodule, …) changed (T),status commandiff-index command

Skip Link

Created Jun 01 - 08:41

A skip link is a anchor link that permits to jump in the tab order to: an element or from one element to another The scroll is created by a anchor with a fragment uri. Example With bootstrap 5 and the visually-hidden-focusable class (the control b...

Chrome Cli

Created May 26 - 10:59

chrome in headless mode can be used as a CLI Example Taking screenshot Size of a standard letterhead Printing the DOM The --dump-dom flag prints document.body.innerHTML to stdout: Create a PDF The --print-to-pdf flag creates a PDF of the page: REPL ...

Chrome DevTool protocol (CDP)

Created May 25 - 16:30

The is a API that permits to call browsers implementing the CDP api (chrome of course but also any other browser implementation ) via json RPC. The protocol is used to communicate with Chrome and drive the headless browser instance. Usagewebdriverpu...

Data all the way

Always keep one hand firmly on data, Amos liked to say.

Data is what set psychology apart from philosophy, and physics from metaphysics.

Amos Tversky (The undoing project)

Data Warehouse Subsystems

Developing a data warehouse means assembling a lot of subsystems in order to create a whole and coherent data application.

Discovers the 34 Kimball Subsystems and drill down to discover them

Data Warehouse Subsystems

Data Processing

Data processing has changed a lot since 1940 :) and luckily, we are not using punch card anymore.

Stream processing is becoming the norm in data integration task while batch processing stays the king in data analysis.

Data Processing

ENIAC, 1946

The first fully electronic digital computer

Data Modeling

Data Modeling is the translation of process into the world of data. The process is tricky but not insurmountable.

Data Modeling

Dimensional Data Modeling

Dimensional Data Modeling permits you to model a (hyper)cube and analyse a process through different perspective. You define dimensions, measures and metrics.

Dimensional Data Modeling

Most programs process some input to produce some output; that’s pretty much the definition of computing.


A Function is the basic block of all reusable code component. It is also becoming the central component of any serverless architecture.


Knowledge isn't free. You have to pay attention.

Computing Division at the Department of the Treasury, mid 1920s

Table / Relation

The table format (known also as a relation) is the most important data structure used in data analysis. Did you know that its name originate from the medieval counting table ?


Education isn't something you can finish.

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