A is to B as C is to D - in a logical world, no information is given about the relationship of A to C.
In the media, even the "techy" media or the "nerdy" media, an analogy is ALL about the relationship of A to C. Hence we see scads of NOLO's (non-logicals) screaming - They're comparing the internet to double-stuffed Oreos! They're comparing Immigrants to Skittles!
Just take a logic 110 course - PUH-lease!
Oracle - MySQL = PL/SQL.
PL/SQL is a full-blown programming language apart from ANSI SQL. There are objects, table variables, maps, arrays, etc. This is what makes it very hard to switch from Oracle. Once you have been bitten by the PL/SQL bug, it is very expensive to move away from.