Ben Chuanlong Du's Blog

It is never too late to learn.

Conda Build Issue

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

I encountered an issue building the package sqlalchemy-teradata. There are a few related issues: issues/2790, issues/2826. It seems that the recipe uses an outdated URL. Change the URL to …

Developing GUI Applications Using Qt5

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

Installation on Ubuntu

wajig install qt5-default

Crop an Image in Qt

https://stackoverflow.com/questions/7010611/how-can-i-crop-an-image-in-qt

References

https://wiki.qt.io/Install_Qt_5_on_Ubuntu

Tips on ANTLR4

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

Install ANTLR4 in Ubuntu

wajig install antlr4
sudo pip3 install antlr4-python3-runtime==4.5

References

Tips on Maven

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

The Central Repository

$HOME/.m2

maven: shade plugin, scala compile plugin, exclude manifest files, ...

import as maven project ...

find an updated version of scala archetype for maven

mvn package  
mvn clean …

Connect to MySQL Using PyMySQL

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

sudo pip3 install PyMySQL

Tricks

  1. Connection in PyMySQL is not autocommit by default. You must commit to save your changes.

    # suppose conn is the connection object
    conn.commit()
    
  2. parameterized sql: %s …