Node.js, Hapi nodejs framework, MySQL connector/Node.js XDevAPI, connection, connection pool — Today I tried to connect a node.js Hapi Server with mySQL 8 database via X DevAPI. I was excited by mySQL 8’s X protocol/X plugin/X DevAPI tool chain because it seems to have taken care of the Object-Relational Mapping layer all together. Does it?! Here are some basic concepts: X…

Once in a while, one wants to put several github repositories together for various use cases: Organization: Put related repos into one master repository for easy access and reference Merge code from two repos: Merge changes from two repositories together, keeping the history of both Reuse code from another repo…

I used pentaho Data Integration extensively for ETL in data warehousing on a PC before, but want to use it in a Mac now. I followed this instruction to install pentaho 9.0 on a Macbook pro today. I used these two articles as references but had to adjust in two…

D3 stands for Data-Driven Documents. It is a javascript library for creating visualization for your data using html, svg and css. D3 is considered one of the most sophisticated tool for infographics. Here are some infographics made by D3. Streamgraph Transitions Streamgraph Transitions See also a more practical static streamgraph.observablehq.com Zoomable Circle Packing Zoomable Circle Packing Click to zoom in or out.observablehq.com

To create a new rails application, one does: rails new my_app This one-line command installs 106 items at total size 315MB in a my_app directory, and lays out the framework for a basic web app. Many things are installed in this folder, including Rack, ActiveRecord, ActiveModel, ActiveView — the major…

This method connecting an existing database with an rail project. It basically hijacked Rails’ “generate model” functionality to connect an existing database to Active Record. A initial “generate model” creates a migration file, which we will use db:migrate to create the schema.rb for ActiveRecord . To prepare for this to…