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Hi guys, what’s up? I’ll share with you some things that I’ve been reading lately and I think relevant and worthy to take a look:


  • Liquibase is a database version control tool. Supports changesets, branching and merging and also has traceability. It supports the following file formats: XML, JSON, YAML and SQL. Here is an example taken from the official site:

--liquibase formatted sql

--changeset nvoxland:1
create table person (
id int not null primary key,
firstname varchar(80),
lastname varchar(80) not null,
state varchar(2)

--changeset nvoxland:2
alter table person add column username varchar(8)

--changeset nvoxland:3
create table state AS SELECT DISTINCT state AS id FROM person WHERE state IS NOT NULL;
alter table state modify id char(2) NOT NULL;
alter table state add primary key(id);
alter table person add constraint fk_person_state foreign key (state) references state(id);

  • State of the Study: I intend to use, first to test and use the features. If I like, I want to use whenever I can.
  • My Opinion About the Subject: Anything that makes easier database maintenance is valid. Before this, I only used Flyway, but I will test Liquibase.

My Reference Link (BR): https://dicasdolampada.wordpress.com/2012/03/19/evoluindo-o-banco-de-dados-com-o-liquibase/

My Reference Link (EN): https://blog.codecentric.de/en/2015/01/managing-database-migrations-using-liquibase/

Ionic vs React Native

  • Ionic and React Native are two frameworks that promise to develop hybrid mobile applications using JavaScript (Ionic using Angular base, and the React Native using React and its concepts). As I know little of both, I am evaluating pros and cons to know what I should study.

  • State of the Study: I used React Native during this week and I had some difficulties. Studying the difference between the two, the Ionic seems more easy and I intend to use it to get a better opinion.
  • My Opinion About the Subject: I really enjoyed using Ionic and I think it’s better than React Native, being pure Angular and the fact I am already used to Angular. The features that most caught my attention:
    • I really like the concept of Write Once, Run Anywhere, something that does not happen in React Native.
    • Angular, HTML and CSS, really. Maybe that’s the reason for having a large community with plenty of examples of use. It seems more used by the community.
    • Definitely the best thing for me was being able to test on Browser and very little configuration. It took more than a day just setting Android Studio and other things needed to React Native, while the Ionic was a matter of minutes I was already testing the application. I highly recommend it.

My Reference Link: https://www.codementor.io/react-js/tutorial/react-native-vs-ionic


  • Crawling is the technique of extracting data from a given page. Lately I’ve read enough about it and developed a web crawler in Python, but without using the main framework (Scrapy).
  • State of the Study: Although not used Scrapy, I read how it works and read the book cited in the reference link. I learned a lot about it and believe it’s a must-read for anyone who deal with crawling.
  • My Opinion About the Subject: I learned that Crawling is so much more than just get data from a given page. There are several concepts and problems about it, like pages that load data via JavaScript, creating an intelligence to get more pages containing the necessary data, using asynchronous calls and why use, among others. It was a great experience.

My Reference Link: https://www.packtpub.com/big-data-and-business-intelligence/web-scraping-python

Perfomance/Load Tests

  • After the last post about performance tips, I have researched performance/load testing tools to be able to put some things in numbers. I have learned some pretty cool tools and compared them, and soon I intend to do a post about them.
  • State of the Study: I’m currently creating a project in my GitHub (which I will also make available to you) to use as a parameter for the test tools. I already tested 2 tools and I’m testing the third. When I have everything ready, I’ll make a post telling about them and comparing them.
  • My Opinion About the Subject: I like to do functional testing (unit, integration and system), but it is also good to do non-functional testing. I want to find a tool that is very good and I want to test and compare some.

My Reference Link: http://techbeacon.com/web-performance-testing-top-12-free-open-source-tools-consider

That’s it, I hope you liked, and if possible, share something that you’ve been reading. Bye.