Bro there is nothing like SQL and Oracle DEV... these are the name of technology in which you going to do some development work.... to be a dev of any database technology you need to learn SQL first, then you have to learn that DBMS system (SQL Server,Oracle, MysQL etc) after that you will be called of that dbms developer like you said sql dev or oracle dev... So it is up to you which dbms you will choose...dev part is almost same for both... but admin part is differ..hope this will help you to understand the concept...