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Smart Contract in Ethereum Blockchain   TABLE OF CONTENTS (HIDE) Writing Smart Contracts in Ethereum Blockchain   To program Ethereum blockchain, you need to be familiar with JavaScript and full-stack web development under Node.js. Introduction to Blockchain Technology [Work In Progres] A blockchain is a distributed digital ledger of transactions . It contains records of all transactions or events that have been executed, which are shared across the nodes participating in the blockchain. A blockchain is segregated into blocks. Each block contains encypted data on the transaction, sender/receiver, and the previous block's hash. The block is then appended to the chain in chronological order, hence, the name blockchain. Blockchain is immutable and trusted ... Blockchain is distributed, peer-to-peer, decentralized, not controlled by an single party, no intermediary to verify. Consensus algorithms (to prevent double-spending): Proof of Work (PoW): For each block ge...

PostgreSQL Getting Started   TABLE OF CONTENTS (HIDE) Getting Started with PostgreSQL I assume that you are familiar with SQL commands (such as CREATE TABLE, DROP TABLE, INSERT, SELECT, UPDATE and DELETE). Otherwise, read ... Introduction PostgreSQL is an open-source Object-Relational Database Management System (ORDBMS). It supports a large part of the SQL standards such as foreign keys, triggers, views and transactions; and object-oriented features such as inheritance. The project started in UC Berkeley in 1986, and is now developed by a group of volunteers called "PostgreSQL Global Development Group". The mother site for PostgreSQL is http://www.postgresql.org ; with manual @ http://www.postgresql.org/docs/manuals/ . Installing PostgreSQL 10.6 Ubuntu // Refresh the apt-get repository $ sudo apt-get update // Install PostgreSQL $ sudo apt-get install postgresql postgresql-contrib // Verify the installation $ dpkg --status postgresql Package: postgresql...