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I'm back with a very quick addition.

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This is a frequently asked question that I get pretty often, which is, is there really a big difference

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between right and left joints?

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If we just change the order of what we're joining and the answer is no, they're actually the same.

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So if we do a left join where this is customers A and then on the right we have orders that's identical

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to doing a right join.

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If instead we put customers over here and we put orders under a so think of it as just flipping this.

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There's no difference.

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So let me show you an example.

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If we go and we go grab our simple left, join from way back here.

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This one right here are simplest left join and I will paste it down here just so you have it to see

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and let's paste it in as well.

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Okay.

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First of all, there's a lot to look at, right?

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But what's most important is that we have on the left customers information first, and then on the

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right we have our order information right.

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And then we have nulls where we don't have a matching order.

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So what happens if we try and do the same thing?

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But instead of doing customers first, we do orders and we do a right join customers on customers ID

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equals orders dot customer ID.

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So if we do this.

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Look at what we get here.

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So we have the exact same data.

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One, two, three, four, five rows.

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One, two, three, four, five.

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But the order that they're printed is different, right?

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So we have on the left side now we have our orders, information.

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And then on the right, we have our customers information.

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But the actual data that's displayed is the same.

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Yes, the order changes.

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But that's trivial.

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That doesn't matter.

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So in effect, these are equivalent.

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And in fact, some like some environments that I've come across, some developing environments won't

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even support a right join.

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And they just want you to do a left join and switch the order.

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So to actually to sum up one more time, let's say I did the same thing here with orders and customers,

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but I did a left join.

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What would happen now?

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What's a left join with orders first and then customers.

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And the answer is it's the same as doing a right join, except if we start with customers and then orders.

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And unfortunately, we don't really have anything to see.

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Right, because our data doesn't have any discrepancies on the order side.

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This is what the entire last video is about, which I will not retread here.

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But my point is that they look the same and they look just like an inner join as well.

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But when we have something different, like with our left join for customers and orders, you can see

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that the data is actually the same.