I finally got to a point in my self study book where the topics seemed familiar. It was still good to review and learn a couple more facts.PL/SQL is strongly typed. You have to specify a type for variables. And once that type is set, you cannot change the variable type.
Variables that are not initialized start out as NULL. Here are some important truth table facts for boolean logic with NULLs:
TRUE AND NULL = NULL
FALSE AND NULL = FALSE
TRUE OR NULL = TRUE
FALSE OR NULL = NULL
I learned a couple more facts and tricks. But perhaps I will save it for another post. This is the good stuff. I love PL/SQL programming.
