Do you know if it's PLSQL? I assume it is since it's Oracle, but I do not trust that it's not something entirely different

Sort of. You can only run SELECT statements, so any sort of scripting or use of cursors on the NetSuite side isn't possible. However, you can use some Oracle-specific functions and syntax, in addition to ANSI SQL, such as the Oracle REGEXP_* functions. In order to do any real scripting, you need an intermediate database where you can populate temp tables, replicate data, define variables and cursors, etc. Our company uses SQL Server primarily, and we use T-SQL scripts and SSIS for more advanced functionality.