How do you make a simple, secure DataStore?

I've heard that UpdateAsync() is better SetAsync(). It's confusing for me, can someone explain it detail? thanks.

UpdateAsync() Takes whatever data whichever datastore already as, SetAsync() sets the data to something ignoring what data already existed. If either one fails, UpdateAsync() will simply leave the players data as it was before; SetAsync() will delete that players data. That is why UpdateAsync() is better.

The following codes will give you a Coins & Wins datastore system; place them in parts in Workspace/ServerScriptService

local DataStoreService = game:GetService("DataStoreService")
local myDataStore = DataStoreService:GetDataStore("swginerreberbree7tdg") 

game.Players.PlayerAdded:Connect(function(player)

	
	local Wins = Instance.new("IntValue")
	Wins.Name = "Wins"                      
	Wins.Parent = player:WaitForChild("leaderstats")
	
	
	
	local playerUserId = "Player_"..player.UserId
	
	
	-- Load data
	local data
	local success, errormessage = pcall(function()     
		 data = myDataStore:GetAsync(playerUserId) 
	end)
	
	if success then
		Wins.Value = data 
	end	
	
	Wins.Changed:Connect(function()
		
		print("Wins changed, saving...")
		
		local playerUserId = "Player_"..player.UserId        
	
		local data = player.leaderstats.Wins.Value
	
		local success, errormessage = pcall(function()
			myDataStore:UpdateAsync(playerUserId, function()
	   		return data                                          			
		end)
	end)
end)
end)



game.Players.PlayerRemoving:Connect(function(player)
	local playerUserId = "Player_"..player.UserId        
	
	local data = player.leaderstats.Wins.Value
	
	local success, errormessage = pcall(function()
		myDataStore:UpdateAsync(playerUserId, function()
    return data                                          			
	end)
end)	
	
	if success then
		print("Data successfully saved!")
	else	
		warn("There was an error!")
		error(errormessage)                      
   end
end)

local DataStoreService = game:GetService("DataStoreService")
local myDataStore = DataStoreService:GetDataStore("swgwgrreg4gtne7tdg") 

game.Players.PlayerAdded:Connect(function(player)
	
	local leaderstats = Instance.new("Folder")
	leaderstats.Name = "leaderstats"
	leaderstats.Parent = player
	
	local Points = Instance.new("IntValue")
	Points.Name = "Coins"                      
	Points.Parent = leaderstats
	
	
	
	local playerUserId = "Player_"..player.UserId
	
	
	-- Load data
	local data
	local success, errormessage = pcall(function()     
		 data = myDataStore:GetAsync(playerUserId) 
	end)
	
	if success then
		Points.Value = data 
	end	
	
	Points.Changed:Connect(function()
		
		print("Wins changed, saving...")
		
		local playerUserId = "Player_"..player.UserId        
	
		local data = player.leaderstats.Coins.Value
	
		local success, errormessage = pcall(function()
			myDataStore:UpdateAsync(playerUserId, function()
	   		return data                                          			
		end)
	end)
end)
end)



game.Players.PlayerRemoving:Connect(function(player)
	local playerUserId = "Player_"..player.UserId        
	
	local data = player.leaderstats.Coins.Value
	
	local success, errormessage = pcall(function()
		myDataStore:UpdateAsync(playerUserId, function()
    return data                                          			
	end)
end)	
	
	if success then
		print("Data successfully saved!")
	else	
		warn("There was an error!")
		error(errormessage)                      
   end
end)