Python

vinta/awesome-python

The Little Book of Python Anti-Patterns - Python Anti-Patterns documentation

TheAlgorithms/Python

Python Design Patterns

Linux

LinuxCommand.org: Resources

BashGuide

The Missing Semester of Your CS Education

CMU Great Practical Ideas in CS

Databases

CMU 15-445/645 :: Intro to Database Systems (Fall 2019)

CS186Berkeley

Modern SQL: A lot has changed since SQL-92

SQL Indexing and Tuning e-Book for developers: Use The Index, Luke covers Oracle, MySQL, PostgreSQL, SQL Server, ...

PostgreSQL Tutorial

Mode SQL Tutorial