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Here's a quick solution to the delete exercise.

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First up, delete all four year old cats.

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So like I said, I like to make sure I can select those first select star from cats where age equals

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exactly four.

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And it looks like there's just one of them ages four.

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Ringo Great.

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So instead of doing a select star, I'm going to do a delete from cats where age equals four.

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And I should also get some confirmation, right?

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I see one row affected.

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That is a very it's an understatement.

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It wasn't just affected, it was removed.

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If I do a select star from cats, we'll see.

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Ringo is just gone entirely now.

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And if I tried to rerun that query from earlier, a couple of lines to go select Star from Cats where

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age is four, we get an empty set.

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We have no resulting rows.

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Next, delete the cats whose age is the same as their cat ID.

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So once again, I like to start with a select select start from cats.

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And then where age is equal to cat ID.

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We saw this when we talked about selecting with where we can do things like two different column names

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and compare them.

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Now there's only one matching cat.

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So we see Jack cat idea seven age of seven.

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Well, we're going to delete you, Cat.

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I mean, Jack, technically, also cat delete from cats where age equals cat ID If I try to run my select

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again, it's gone.

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Select star from cats.

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We're now down to four cats.

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I deleted Egg in the intro to deletion video just in case you're wondering how we went from 7 to 4.

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Well, now we're going to go from four to knockouts, delete all of them.

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And this one, simple enough.

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You just want to be careful with this.

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If I do delete from cats and nothing else, they're all gone.

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So be careful if you have data you care about.

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But we don't have anything we care about.

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I'm sorry, cats.

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We've shut down the shelter and euthanized all of you.

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Goodbye.

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Now we look at cats.

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Nothing in there.

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Och, that's it.

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Next up, we've got a much bigger exercise to put it all together.