Data Store

1. What is a DataStore?

A DataStore is Roblox's system for permanently storing player data.

the script goes in serverscriptservice

2. Where DataStores are used

Pretty much anything you want the game to remember.

Examples:

Coins
Level
XP
Inventory
Weapons
Pets
Achievements
Quests
Settings
Wins
Kills
Checkpoints
Stats
Game progress

3. DataStores are Server-Side

This is important.

You should use DataStores from a server Script, not a LocalScript.

Server
└── Script
     ↓
  DataStore

You don't want the client directly controlling saved data.

4. Getting DataStoreService

You start by getting Roblox's DataStoreService.

local DataStoreService = game:GetService("DataStoreService")

Then you create/get a DataStore:

local playerData = DataStoreService:GetDataStore("PlayerData")

Think of "PlayerData" as the name of your database.

DataStoreService
       ↓
   "PlayerData"
       ↓
Player information

What is pcall()?

pcall() means:

Protected Call

It allows you to run code that might produce an error without crashing your script.

Basic structure:

local success, result = pcall(function()

	-- Code that might fail

end)

Using pcall() With DataStores

This is where it becomes useful.

Instead of:

local data = playerData:GetAsync(key)

you do:

local success, data = pcall(function()

	return playerData:GetAsync(key)

end)

Then check:

if success then

	print("Data loaded!")

else

	warn("Failed to load data:", data)

end

A common pattern is:

local success, result = pcall(function()
	-- DataStore operation
end)

if success then
	-- It worked
else
	-- Handle the failure
end

Example

local dataStoreService = game:GetService("DataStoreService")

local playerCoins = dataStoreService:GetDataStore("PlayerCoins")
local playerInventory = dataStoreService:GetDataStore("PlayerInventory", "Coins")


game.Players.PlayerAdded:Connect(function(plr)
	local leaderstats = Instance.new("Folder", plr)
	leaderstats.Name = "leaderstats"
	
	local coins = Instance.new("IntValue", leaderstats)
	coins.Name = "Coins"
	coins.Value = 0

	local success, currentCoins = pcall(function()
		
		return playerCoins:GetAsync(plr.UserId) //getting the ID is the best option
		
	end)
	
	if success then
		coins.Value = currentCoins
	else
		coins.Value = 0
	end
	
	local success, updatedValue = pcall(function()
		return playerCoins:IncrementAsync(plr.UserId, 100)
	end)
	
	if success then
		coins.Value = updatedValue
	end
	
end)