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Welcome back.

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In this lecture we're going to continue to learn about data stores by understanding what an ordered

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data store is.

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Sometimes when we create games, we would like to create a universal leaderboard that shows like the

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top ten players in a specific category, like top ten with most kills, top ten with the most money,

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and so on.

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And we can do so by storing player data within an ordered data store.

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Now, if you remember inside of our leaderboard handler, we created our money data store by using the

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Get Data Store function.

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However, the data store that is returned by this function is not an ordered data store, meaning we

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are unable to do things like grab the top ten players.

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So we need to swap this out with an ordered data store instead of a regular data store.

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To do this, there is another function within the data store service called Get Order Data Store.

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So I'm going to create a new variable.

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I'm going to call this one Ordered Money Data Store.

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And that's going to be equal to the data store service get order data store.

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And for this one we can just call it like player money.

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However, note that this is going to be creating an entirely new data store, and any data store that

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was stored in this previous data store will not show up in this ordered one.

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So you need to make sure that you plan out what data you would like to store in an ordered data store

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before you start scripting your game, because it will be very hard to migrate data later.

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Now that we have this new ordered data store, I'm going to copy this and update the references within

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my scripts.

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So I don't want to get money data from our money data store anymore.

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Instead, we're going to be using the Order Data Store.

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And we're also going to be using the Order Data Store for saving money data.

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And this ordered money data store has the exact same functions as a regular data store, such as update

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async.

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We also have set async, get async, and then it also has the standard function of remove async.

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And I don't believe I talked about this function last time, but this one's very simple.

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All you need to do is pass a key in here, and if it finds the key in the table, then it completely

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removes that key and its value from the data store.

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So that's what that function does.

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But this ordered money data store has another function inside of it that we get to use.

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And this function is called Get sorted async.

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And it says it returns a data store pages object.

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So what we do in this function is we specify if we would like to grab, um, data in ascending or descending

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order.

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In this case, since we want to grab the top ten players, then we need to keep ascending at false.

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We can specify the page size or the number of keys that we would like to grab.

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So if we would like to grab the top ten players then we would pass the number ten here.

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And then there's some other optional data such as a minimum value stored at those keys, and a maximum

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value.

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So if any value stored does not match this minimum value or any value goes above the max value, then

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it's going to ignore that key.

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And it's not going to be included in this data store pages object.

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So what I'm going to do is I'm going to create a new function.

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And I'm going to call this function get top money players.

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And I want this function to return to me a data store page that has the top five players.

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So what we need to do is we need to refer to our ordered money data store and use the get sorted async

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function.

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We want to keep it descending.

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So we're going to set this false for the ascending boolean.

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And then we want to grab let's say the top five players with the most money.

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Now since this is an async function, that means we also need to wrap it in a p call.

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So we'll do p call, pass a function here, and then we'll control and x this and then return the value

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returned from our ordered money data store will store this in the success and then the result variable.

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And if we weren't successful in grabbing the top five players, then we'll just warn in the console.

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Fail to grab top players.

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And I'll just return.

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Otherwise we can go ahead and get the top five players from the result.

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And since this returns it says a data store pages object.

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Let's go ahead and go over to the Roblox API to see what the functions are for a data store pages object.

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So here in the Roblox documentation, it has a data store pages and it says a special type of pages

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object whose pages contain key value pairs from an ordered data store.

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For this object, the function get current page returns an array of tables, each containing keys named

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key and value.

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These reflect the key value pair data.

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So it says right here.

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And here's our example.

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When we get our data store pages object, we have to use a function called get current page to get.

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For example here they're getting a top ten.

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And then they loop through this top ten.

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It shows the rank or the index as well as the data stored at that rank.

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So for example the number one player would have their data and that data would represent the key and

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the value.

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So the key would be the player's user ID.

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And then the value would be how much money they have.

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So we can go ahead and implement this into our script.

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So once we get this result from our ordered money data store, the function is said to use is get current

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page.

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And this is going to return to us, our top five players.

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And I'm going to go ahead and return these top five players out of our function.

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And then what I'm going to do simply for demonstration purposes is I'm going to scroll down and before

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our while loop, I'm just going to yield for five seconds.

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And then we're going to go ahead and get the result from our Get Top Money players function.

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And then we're going to go ahead and loop and get every single rank and data inside of our result.

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And from here we can go ahead and print out into the console something like player, and then we can

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pass the key.

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Remember this data object or this table right here has a key called key.

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So this would be our player's user ID.

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So player with this user id we can say they are the rank or is rank.

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And then we could pass the rank which would be this value right here.

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And then we can say how much money they have.

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So player with this user ID is rank let's say rank number one with how much money do they have.

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And then we could pass the data dot value.

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And then we could say they have this many dollars.

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So five seconds after I joined the game, it should grab the top five players inside of our data store

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and then it'll print into the console the top five players.

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Since this is a newly created data store, there shouldn't be any data stored inside of here, meaning

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this shouldn't print.

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So what I need to do is I need to join the game.

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I need to set some money for my player, leave the game and save that data and then rejoin again.

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So let's go ahead and play test the game.

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And since we're using that new data store, of course I have zero money, but I'm going to go ahead

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and update the value inside of here.

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We could set it to something like 1000.

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And then I can go ahead and leave the game to save that data.

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And now I can go back and play my game again.

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Here we have my $1,000 and it should print into the console.

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There we go.

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Player there is.

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My user ID is ranked number one with $1,000.

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And just like that, we have successfully grabbed the top players in our game with the most money.

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Now you can do a lot with this data.

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You could update a surface UI that shows all the top players in your game with the most money.

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There's a whole bunch of different stuff you can do with it.

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It's really up to your own creative preference.

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Otherwise that's how simple it is to use ordered data stores.

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Not much more than that.

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Keep up the good work and I'll see you in the next one.