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Next up, we're going to talk about some logical operators that are built into MySQL that help us write

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more complex queries and more complicated logic.

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For example, a simple thing that we could do by the end of this section is select all the books not

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published in 2017.

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We know how to publish or select books published in 2017, but what about the opposite?

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Or select all birthdays between 1990 and 1992?

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Or select all the items that are in stock and also have a price under 1999.

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So these are still relatively simple, but there's building blocks that we're going to cover things

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like not and between and and so we'll get there.

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We're going to start in this video with not equal.

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So an exclamation point in front of the equal sign means not equal.

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In this example, I'm selecting the title from books where the year is not 2017.

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So of course we know how to do select star from books where I think it's released year is equal to what

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did I say, 2017.

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There we go.

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Lincoln in the Bardo 2017.

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There's one book Row 19 But if I put an exclamation point in front of that equal sign, that now means

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not equal.

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So we'll select any books where release year is anything but 2017.

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So we get a bunch of them, as you can see here, but we won't have 2017, so we're missing that row.

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It might be a little harder to tell, but why don't we try another example?

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Let's select title and author, last name from books, and let's select all the books that were not

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written by Gaiman, Neil Gaiman.

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So we'll just use the last name.

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So I would do something like select title and author, last name from books where author L name.

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And instead of saying it's equal to Gaiman, of course that's going to give me Neil Gaiman's three books.

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Oh, I spelled it wrong, gay man like that.

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GAIMAN Instead of that, we're going to just put an exclamation point to invert the meaning of this.

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Now, again, author last name can be anything except Neil Gaiman or just Gaiman.

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And we see all of the books, minus the Gaiman books.

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So there's a smaller group.

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You still just have to kind of trust that it works, but you can see there's no Gaiman here versus here.

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You know, we had Gaiman, Gaiman and Gaiman there.

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So that's our first example of a logical operator.

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We've actually already seen a quality which is a logical operator as well, the single equal sign.

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But when we put that bang in front of it or the exclamation point, it means not equal.

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So next step, we're going to keep learning some more of these operators.