It's not ranked..
Oracle:
APEX - Oracle Forums
https://apex.oracle.com/en/community/ideas/
https://blogs.oracle.com/apex/
not apex .. but other cool stuff
https://www.thatjeffsmith.com/
Community: you will find a lot of great bloggers on this pages
apex.world
Oracle APEX & ORDS Blogs (cloudnueva.com)
Oracle APEX Shorts - Innovative Insights into the Oracle APEX, REST Data Services (ORDS), Database and OCI (cloudnueva.com)
not only apex .. but other cool stuff
https://oracle-base.com
Favorit Youtubechannels:
SQL and Databaseexplained! - YouTube
Oracle Apex & database - YouTube
Also look here, if you like more content :)
Sphinx Blog