O  Oracle 23c Free  is out. I am so excited about this, because it is marking a great shift. Usually we got just few new features and improvements after several years of waiting. Now it seems like it is more focused on the developers. A huge improvements, released firstly to developers and later to customers. Exciting.   So we have great and always free Oracle Cloud  option and now we have Oracle 23c Free  as an on premise option. How cool is that?    What to love?     Boolean data types in SQL  (finally)    Aliases in GROUP BY and HAVING clauses    Conditional DDL (IF NOT EXIST)    Simplified data creation    End of DUAL , I will miss this little quirk    SQL subtypes (domains)    and huge JSON improvements     You can check Tim Hall's articles  on 23c. You can download prebuilt VirtualBox image  from Oracle, also with SQLcl 23.1 and APEX 22.2 or Tim's Vagrant build  and this one also covering Docker  by Gerald.     
Mainly APEX, sometimes SQL, PL/SQL, clean code and certifications