
Microsoft SQL
MySQL
PostgreSQL
Oracle Database 12c
Oracle DBaaS
SQLite
SAP HANA
Software AG webMethods
SmartCards+
Mochi
CleverDeck
Anki
Yak Tack
Harken
Zorbi - Spaced-Repetition Flashcards
Quizlet
Microsoft SQL
SmartCards+MySQL - The world's most popular open source database
Mochi - Write notes and flashcards with Markdown and study them with spaced repetition.
PostgreSQL - PostgreSQL is a powerful, open source object-relational database system.
CleverDeck - Learn languages more efficiently with spaced repetition
Oracle Database 12c - Simplify database management and automate the information lifecycle with maximum security.
Anki - Anki is a program which makes remembering things easy. Because it's a lot more efficient than traditional study methods, you can either greatly decrease your time spent studying, or greatly increase the amount you learn.