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One rule of thumb that I like to share with students is just to be careful with what you're updating

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in general, right?

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You can do these mass updates and change everything in a table, which could be useful sometimes, but

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a lot of the time it's actually accidental.

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So to prevent any unexpected updates, I recommend that you select whatever you're trying to update

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before you actually perform the update.

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So if we go back to something like what we had right here, I updated cats to set age to be 14 where

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name is set to Misty.

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I could just trust that this is going to select what I expect.

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But maybe there's more than one cat called Misty and I don't want to have them both update to have their

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age set to 14.

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I mean, maybe they have the same birthday on the same day.

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But if that's not what I'm anticipating, it's best to try the query out and try this way or portion

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out before I update anything.

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So I could just copy that and then try doing instead of select star from cats.

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Especially if I have like thousands of cats, select star from cats.

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Add my query.

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The where portions.

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It's not actually a full query, but at this where clause at the end and make sure this is what I want

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to target with my update.

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And if it is, then I go ahead and run that query, update it to have age 14, age was already set to

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14 for that row, so it doesn't really matter.

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But the point is that instead of just diving right into an update and the same will go for a deletion

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as well when we get there, I recommend selecting testing out your WHERE clause.

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Make sure you're getting the data you're expecting to update or you're expecting to to delete before

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you perform those operations.

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You don't always have to do that, but it's just something I recommend, especially when you're learning

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SQL.