So, I’ve just recently gotten back into scripting and am working on a sandbox-based tycoon for learning purposes, as it seems such will require me to know a lot. 
I’ve practically gotten my datastore system up and ready, though I’m still adjusting a lot and implementing features I’ve forgotten/think I may need in the future. I’ve based it on the same saving methods that datastore 2 uses (As I’m sure you can tell.), and so far my implementation of it seems to be working well, but I haven’t tested it with large amounts of data yet.
I’m looking for any input on improvements I can make, or any issues that you think it could present in the future. Some specific parts I am slightly concerned about, is the updateData and retrieveData methods, I feel like there has to be a better way for those to work, though I am not sure.
local datastoreservice = game:GetService("DataStoreService")
local datasettings = require(game:GetService("ServerScriptService").settings.dataStoreSettings)
local loadedData = {}
local dataPreset = {inventory = {}, currencies = {coins = 100, gems = 25}, base = {}}
local dataModule = {}
function dataModule.getSaveList(plr)
local saves = datastoreservice:GetOrderedDataStore(datasettings.version..plr.UserId)
local pages = saves:GetSortedAsync(false, 5)
local currentpage = pages:GetCurrentPage()
local keys = {}
for _, v in ipairs(currentpage) do
table.insert(keys, {v.key, v.value})
end
return keys
end
function dataModule.getSelectedData(plr, key)
local loaded = false
for _, v in ipairs(loadedData) do
if v.id == plr.UserId then
loaded = true
break
end
end
if loaded == true then
return true
end
local datastore = datastoreservice:GetDataStore(datasettings.version..plr.UserId)
local selecteddata = datastore:GetAsync(key)
if selecteddata then
table.insert(loadedData, {id = plr.UserId, userdata = selecteddata})
print("Successfully loaded data for..."..plr.Name)
return true
else
return false
end
end
function dataModule.saveLatestData(plr, unload)
local savetime = os.time()
local userdata
for _, v in ipairs(loadedData) do
if v.id == plr.UserId then
userdata = v.userdata
break
end
end
if not userdata then
print("No loaded data for..."..plr.Name)
return "nodata"
end
local datastore = datastoreservice:GetDataStore(datasettings.version..plr.UserId)
local saves = datastoreservice:GetOrderedDataStore(datasettings.version..plr.UserId)
local success, err = pcall(function()
datastore:SetAsync("save"..savetime, userdata)
saves:SetAsync("save"..savetime, savetime)
end)
if not success then
print("Failed to save data for..."..plr.Name.."...retrying.")
wait(5)
dataModule.saveLatestData(plr, true)
else
print("Successfully saved data for..."..plr.Name)
dataModule.unloadData(plr)
end
end
function dataModule.getPreset(plr)
dataModule.unloadData(plr)
table.insert(loadedData, {id = plr.UserId, userdata = dataPreset})
print("Preset data loaded for..."..plr.Name)
end
function dataModule.unloadData(plr)
for n, v in ipairs(loadedData) do
if v.id == plr.UserId then
table.remove(loadedData, n)
print("Data unloaded for..."..plr.Name)
break
end
end
end
function dataModule.retrieveData(plr, key, key2)
for _, v in ipairs(loadedData) do
if v.id == plr.UserId then
--Checking if it is retrieving a specific segment of data or just all of it.
if key == "all" then
return v
end
if not key2 then
return v.userdata[key]
else
return v.userdata[key][key2]
end
end
end
end
function dataModule.updateData(plr, key, key2, change)
for _, v in ipairs(loadedData) do
if v.id == plr.UserId then
--Checking to see if we are updating data one layer deep or two.
if not key2 then
--Checking the type of data inputted as it does different things based on the results.
if type(change) == "table" or "string" or "boolean" then
v.userdata[key] = change
elseif type(change) == "number" then
v.userdata[key] = v.userdata[key] + change
end
return v.userdata[key]
else
if type(change) == "table" or "string" or "boolean" then
v.userdata[key][key2] = change
elseif type(change) == "number" then
v.userdata[key][key2] = v.userdata[key][key2] + change
end
return v.userdata[key][key2]
end
end
end
end
return dataModule