Theory can you can you say hello Hello It's me.
I was wondering if after all these years you'd like to meet to go over everything.
They say that this is too much.
Thank you Siri.
Can you just say hello.
Not singing it wants me to say hello and welcome to the next section.
Thank you Sherry.
So Siri said Hi welcome to the next section.
This section is all about logical operators.
So if you come from a programming language do you have any programming experience.
You have probably stumbled across logical operators.
Things like logical and logical or there's a bunch others but those are the primary two.
If you haven't if you have no idea what I'm talking about don't panic.
That's what this section is all about.
So this will either serve as a review if you know how to program or if you know of logical operators
and it will serve as a way to show you how they work.
In my ask you will or it will serve to both introduce them and to show you how they work.
In my school.
Either way they're really powerful.
I'm not going to say they're important they are important but I'm just over using that phrase in these
videos.
Everything is important here but these allow us to string together different queries and make more complex
selections.
So if I were to give you a really contrived idiotic example like cars and I want to select all cars
based off of a color right now all we could do is select all cars that have a color of exactly blue.
Or a color that contains the word blue.
Like I don't know if Sky Blue or seashore blue or something like that.
That's fine.
But what if you also wanted to select all cars that were blue or that were red.
Again I said contrived and silly but the idea is we can string things together.
So rather than having to do 2 queries we could put them together or if we go to our books example which
by the way we're about to finish with this is the last of that section lots of our books data.
We could make more complex selections like select all books that have a price below $20.
And at the same time there I don't know we have 50 copies in stock or we could do something like select
all books written by a certain author before the year 1990.
So two different components right.
We could select all books before 1990.
Select all books written by a certain author but put them together.
We need to use a logical operator.
All right I'm rambling a little bit.
Apologize.
This section is on logical operators.
Lots of exercises of course like always.
Hopefully they're enjoyable.
If not well like I said it is of course I'm database's So I'm trying I really am yeah.
OK I'm going to stop.