technology:relational database

Building a Fully #serverless Realtime CMS using AWS #appsync and #aurora Serverless
▻https://hackernoon.com/building-a-fully-serverless-realtime-cms-using-aws-appsync-and-aurora-se

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AWS made a serverless option of AWS RDS Aurora generally available, It would mean a breakthrough in building fully serverless architectures with relational database. No more managing connection pools with SQL, No more worrying about RDS instances, Cost is based on the compute time services are consumed, and there is no charge when code is not running.In this post , my goal was to build a fully-functional AWS AppSync-driven backend and #react frontend of a post management app. The app will deliver end users a set of features that allow public users view posts, admin users add/delete post, Let’s start!Application ArchitectureThe application architecture uses:Serverless frameworkAWS AppsyncAWS Cognito Userpool and Identity PoolAWS Aurora ServerlessAWS LambdaPrerequisitesThe following must be (...)

#aws-lambda

#postgresql’s Exciting features, you should know
▻https://hackernoon.com/postgresqls-exciting-features-you-should-know-a516a441b8c4?source=rss---

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PostgreSQL is a powerful,object-relational database system that extends the #sql language combined with many features that safely store and scale the most complicated data workloads.PostgreSQL comes with many features aimed to help developers build applications, administrators to protect data integrity and build fault-tolerant environments, and manage data no matter how big or small the dataset.Here, I pick some great PostgreSQL features you may not have taken a look at but really should, since they can help you get code into production faster, make easier and generally get things done with less code and less effort.InheritanceTable #inheritance allows extracting a common set of columns into a parent table with children defining additional fields.CREATE TABLE invoices ( invoice_number (...)

#postgresql-feature #sharding

Incentive Tracking System
▻https://hackernoon.com/incentive-tracking-system-85935089d356?source=rss----3a8144eabfe3---4

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SourceProblemFor every sale, salesmen are rewarded with an incentive. Tracking these sales is very important. It will help the organization give accurate incentives to the sales executives.When the organization is small with less number of employees, this system can be easily implemented on a traditional relational database.However, the problem arises when the organization is a spread across multiple cities across the globe. That is when we need to have a system which can operate at a global scale and the data in the system can be tracked easily.We cannot remove the incentive system because incentives helps the sales executives to work efficiently and perform even better.Thankfully, enterprise blockchains can help us solve this problem.SolutionAs stated in the previously, I intend to (...)

#incentive-tracking-system #blockchain #game-theory #smart-contracts #incentive-tracking

Using #es6 classes for Sequelize 4 models
▻https://hackernoon.com/using-es6-classes-for-sequelize-4-models-b9fd54a5f8c9?source=rss----3a81

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Photo by Eugene Lim on UnsplashThe ES2015 or ES6 specification introduced class to #javascript. Libraries like React went from React.createClass to class MyComponent extends React.Component, ie went from rolling their own constructor to leveraging a language built-in to convey the programmer’s intent.For a Node.js web application’s persistence layer, a few databases come to mind like MongoDB (possibly paired with mongoose), or a key-value store like Redis.To run a relational database with a Node application, Sequelize, “An easy-to-use multi SQL dialect ORM for Node.js” is a good option. It allows the application to run backed by a MySQL or PostgreSQL instance and provides an easy way to map from entities’ representation in the database to JavaScript and vice versa.Sequelize’s API for model (...)

#nodejs #es6-classes #productiv

Art/Styles and movements - Monoskop
▻https://monoskop.org/Art

Art historians have debated the limits and bias of style analysis and classification for decades.[2] Despite that, the style remains “inseparable from working concepts of art and its history”[3], while its relevance is now being reaffirmed in an unsuspected way—as a database column in an ever-growing number of art collections. Major art museums adopted it as an organising element of their online catalogues.[4]

Museums present their online databases as neutral resources which often lack acknowledgment of editorial work and instead derive their legitimacy from the reputation of the institution.[5] While they increasingly influence how we (and machines) look at and learn about art, their protocols are rarely discussed. In contrast to the tradition of scholarly argumentation, the context in the database is given by the way its data are interconnected, where each item is defined by the set of its relations to other items. Rather than notions supporting the argument, styles and movements are vectors along which an online collection is designed to be viewed, queried, and referred to. This enables databases to position artworks as belonging to particular styles and movements by the mere designation of a relation.[6] Even though art collections databases are heir to the art-historical tradition, they adjust art to the logic of the relational database—the logic of organising data into rows and columns containing items pointing at one another. The same holds for other attributes of artworks, pre-formatted by the database as lists of authors, materials, years of production, and so on.

#art #styles #mouvements :)

GitHub - citusdata/citus: Scalable PostgreSQL for real-time workloads
▻https://github.com/citusdata/citus

What is Citus?

Open-source PostgreSQL extension (not a fork)
Scalable across multiple hosts through sharding and replication
Distributed engine for query parallelization
Highly available in the face of host failures

Citus horizontally scales PostgreSQL across commodity servers using sharding and replication. Its query engine parallelizes incoming SQL queries across these servers to enable real-time responses on large datasets.

Citus extends the underlying database rather than forking it, which gives developers and enterprises the power and familiarity of a traditional relational database. As an extension, Citus supports new PostgreSQL releases, allowing users to benefit from new features while maintaining compatibility with existing PostgreSQL tools. Note that Citus supports many (but not all) SQL commands; see the FAQ for more details.

Common Use-Cases:

Powering real-time analytic dashboards
Exploratory queries on events as they happen
Large dataset archival and reporting
Session analytics (funnels, segmentation, and cohorts)

To learn more, visit citusdata.com and join the mailing list to stay on top of the latest developments.

Using OpenStreetMap Data with Open-Source GIS | Markieta | Cartographic Perspectives

▻http://cartoperspectives.org/index.php/journal/article/view/cp71-markieta/138

INTRODUCTION

For many, free and open-source data and software represents accessibility to otherwise inaccessible geospatial workflows in terms of cost and availability. Commercial data used in geographic information systems (GIS) is available through a relatively small number of merchants or vendors, which produce highly accurate, precise, and detailed information. This is produced, however, at a cost that many small and large businesses, private consultants, and startups cannot afford. Open-source data, such as the volunteer geographic information on OpenStreetMap (OSM), represents a community effort to build one of the best web maps, and subsequently the best GIS database, available for free to the public. OpenStreetMap is a web-based map to which any registered user can submit data. These updates, over time, populate the now extensive web map that is the OpenStreetMap. At the same time, the data that lives on the OpenStreetMap can be downloaded and used inside of a GIS for geospatial analysis, cartographic rendering, and other geo-related tasks.

There are various workflows for extracting and consuming the data that is made available by the OpenStreetMap project. One of these methods is outlined in this tutorial. This tutorial will take Mac OSX users through a typical setup of a local PostgreSQL database, downloading and parsing raw OpenStreetMap data, and querying the database to extract data for use in QGIS, an open-source GIS package. Upon completing this tutorial, users will have hit the ground running, with the ability to run spatial queries—such as locating all the coffee shops within 500 metres of a subway station—or building cartographically pleasing reference map books with data that is of interest to the map reader.
THIS TUTORIAL WILL COVER THE FOLLOWING:

Access and browse an OSM data repositories
Download a subset (often called an “extract”) of the planet.osm data package
Install PostgreSQL (object-relational database system)
Install PostGIS for use with PostgreSQL (spatial database extension for PostgreSQL)
Install and utilize osm2pgsql (converts OSM data for use in the PostgreSQL database)
Install QGIS and its dependencies (GIS package)
Query and add data in QGIS from PostGIS/PostgreSQL

#qgis #gis #osm #logiciels_libres #cartographie

Relational Databases Aren’t Dead. Heck, They’re Not Even Sleeping
▻http://readwrite.com/2013/03/26/relational-databases-far-from-dead

To listen to the media, you would think that the end of the relational database is about to strike at any moment, leaving behind a shattered mess of tables and queries strewn about in proprietary servers, collecting silicon dust.
Truth be told, the future for relational databases has really never been better — …

▻http://readwrite.com/files/styles/150_150sc/public/fields/servers%20in%20data%20center%20shutterstock_85778389.jpg

Source: ReadWrite - Brian Proffitt