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Source: Roblox Creator Hub · CC BY 4.0 · View source · Code samples: MIT Imported 2026-10-03. Formatting adapted for this site.

MemoryStoreSortedMap

Inherits from: Instance → Object

Provides access to a sorted map within MemoryStoreService. A sorted map is a collection of items where string keys are associated with arbitrary values (up to the maximum allowed size -- see Memory Stores). Each item can also have an optional sort key, which can be a number or a string. In the ordering of items, the sort key, if provided, takes precedence over the key. Items with numeric sort keys are sorted before items with string sort keys, which are sorted before items with no sort key. Items with the same sort key and items with no sort key are arranged in alphabetical order by key.

Inherits from: Instance

Memory category: Instances

Tags: NotCreatable, NotReplicated

Methods

Name	Type / Returns	Description
MemoryStoreSortedMap:GetAsync	Tuple	Retrieves the value and sort key of a key in the sorted map.
MemoryStoreSortedMap:GetRangeAsync	Array	Retrieves items within a sorted range of keys and sort keys.
MemoryStoreSortedMap:GetSizeAsync	int	Gets the size of the sorted map.
MemoryStoreSortedMap:RemoveAsync	()	Removes the provided key from the sorted map.
MemoryStoreSortedMap:SetAsync	boolean	Sets the value of a key.
MemoryStoreSortedMap:UpdateAsync	Tuple	Retrieves the value and sort key of a key from a sorted map and updates it with a new value and sort key.

Inherited from Instance

Name	Type / Returns	Description
Instance:AddTag	()	Applies a tag to the instance.
Instance:children	Instances	Returns an array of the object's children.
Instance:ClearAllChildren	()	This method destroys all of an instance's children.
Instance:Clone	Instance	Create a copy of an instance and all its descendants, ignoring instances that are not `Archivable`.
Instance:clone	Instance
Instance:Destroy	()	Sets the `Instance.Parent` property to `nil`, locks the `Instance.Parent` property, disconnects all connections, and calls `Destroy()` on all children.
Instance:destroy	()
Instance:FindFirstAncestor	Instance?	Returns the first ancestor of the `Instance` whose `Instance.Name` is equal to the given name.
Instance:FindFirstAncestorOfClass	Instance?	Returns the first ancestor of the `Instance` whose `Object.ClassName` is equal to the given className.
Instance:FindFirstAncestorWhichIsA	Instance?	Returns the first ancestor of the `Instance` for whom `Object:IsA()` returns true for the given className.
Instance:FindFirstChild	Instance?	Returns the first child of the `Instance` found with the given name.
Instance:findFirstChild	Instance
Instance:FindFirstChildOfClass	Instance?	Returns the first child of the `Instance` whose `ClassName` is equal to the given class name.
Instance:FindFirstChildWhichIsA	Instance?	Returns the first child of the `Instance` for whom `Object:IsA()` returns true for the given className.
Instance:FindFirstDescendant	Instance?	Returns the first descendant found with the given `Instance.Name`.
Instance:GetActor	Actor?	Returns the `Actor` associated with the Instance, if any.
Instance:GetAttribute	Variant	Returns the value which has been assigned to the given attribute name.
Instance:GetAttributeChangedSignal	RBXScriptSignal	Returns an event that fires when the given attribute changes.
Instance:GetAttributes	Dictionary	Returns a dictionary of the instance's attributes.
Instance:GetChildren	Instances	Returns an array containing all of the instance's children.
Instance:getChildren	Instances
Instance:GetDebugId	string	Returns a coded string of the debug ID used internally by Roblox.
Instance:GetDescendants	Instances	Returns an array containing all of the descendants of the instance.
Instance:GetFullName	string	Returns a string describing the instance's ancestry.
Instance:GetStyled	Variant	Returns the styled or explicitly modified value of the specified property, or else the default property value if it hasn't been styled/modified.
Instance:GetStyledPropertyChangedSignal	RBXScriptSignal	Returns an event that fires when the given style property changes on the instance.
Instance:GetTags	Array	Gets an array of all tags applied to the instance.
Instance:HasTag	boolean	Check whether the instance has a given tag.
Instance:IsAncestorOf	boolean	Returns true if an `Instance` is an ancestor of the given descendant.
Instance:IsDescendantOf	boolean	Returns `true` if an `Instance` is a descendant of the given ancestor.
Instance:isDescendantOf	boolean
Instance:IsPropertyModified	boolean	Returns `true` if the value stored in the specified property is not equal to the code-instantiated default.
Instance:QueryDescendants	Instances	Returns an array containing all descendants of the instance that match the `selector` string.
Instance:Remove	()	Sets the object's `Parent` to `nil`, and does the same for all its descendants.
Instance:remove	()
Instance:RemoveTag	()	Removes a tag from the instance.
Instance:ResetPropertyToDefault	()	Resets a property to its default value.
Instance:SetAttribute	()	Sets the attribute with the given name to the given value.
Instance:WaitForChild	Instance	Returns the child of the `Instance` with the given name. If the child does not exist, it will yield the current thread until it does.

Inherited from Object

Name	Type / Returns	Description
Object:GetPropertyChangedSignal	RBXScriptSignal	Get an event that fires when a given property of the object changes.
Object:IsA	boolean	Returns true if an object's class matches or inherits from a given class.
Object:isA	boolean

MemoryStoreSortedMap:GetAsync

Retrieves the value and sort key of a key in the sorted map.

Parameters

Name	Type	Default	Description
key	string		Key whose value and sort key to retrieve.

Returns

Type	Description
Tuple	A tuple of two values: - Key value, or `nil` if there's no item with the specified key. - Sort key, or `nil` if there's no sort key associated with the specified key.

Field	Value
tags	["Yields"]
security	None
thread safety	Unsafe
capabilities	["DataStore"]

MemoryStoreSortedMap:GetRangeAsync

Gets items within a sorted range of keys and sort keys.

Parameters

Name	Type	Description
direction	SortDirection	Sort direction, ascending or descending.
count	int	The number of items to retrieve; the maximum allowed value for this parameter is 200.
exclusiveLowerBound	Variant	(Optional) Lower bound, exclusive, for the returned keys. This is provided as a table where one or both of key and sort key can be specified: { key: string, sortKey: Variant } .
exclusiveUpperBound	Variant	(Optional) Upper bound, exclusive, for the returned keys. This is provided as a table where one or both of key and sort key can be specified: { key: string, sortKey: Variant } .

Returns

Type	Description
Array	Item keys, values and sort keys in the requested range.

Field	Value
tags	["Yields"]
security	None
thread safety	Unsafe
capabilities	["DataStore"]

Code samples: View on Creator Hub (retrieving-memorystore-keys).

MemoryStoreSortedMap:GetSizeAsync

Gets the size of the sorted map.

Returns

Type	Description
int	The number of items currently stored in the sorted map.

Field	Value
tags	["Yields"]
security	None
thread safety	Unsafe
capabilities	["DataStore"]

MemoryStoreSortedMap:RemoveAsync

Removes the provided key from the sorted map.

Parameters

Name	Type	Default	Description
key	string		Key to remove.

Returns

Type	Description
()

Field	Value
tags	["Yields"]
security	None
thread safety	Unsafe
capabilities	["DataStore"]

MemoryStoreSortedMap:SetAsync

Sets the value and sort key of the key overwriting any existing key value and sort key.

Parameters

Name	Type	Description
key	string	Key whose value to set.
value	Variant	Key value to set.
expiration	int64	Item expiration, in seconds. The item is automatically removed from the sorted map once the expiration duration is reached. The maximum expiration time is 45 days (3,888,000 seconds).
sortKey	Variant	(Optional) Sort key to set for this key. Accepted types are a number (integer or decimal) or a string.

Returns

Type	Description
boolean	`true` if the value of an existing key was overwritten, or `false` if a new key was added to the sorted map.

Field	Value
tags	["Yields"]
security	None
thread safety	Unsafe
capabilities	["DataStore"]

MemoryStoreSortedMap:UpdateAsync

Retrieves the value and sort key of a key from a sorted map and lets you update it to a new value and sort key via a callback function.

This method accepts a callback function that transforms the old value and old sort key into the updated value and updated sort key as required. The method retrieves the existing key value and sort key and passes it to the transform function which returns the new value and sort key for the item, with these exceptions:

If the key does not exist, the old value and old sort key passed to the function will be nil.
If the function returns nil, the update is canceled.

The new value and new sort key is saved only if the key was not updated (e.g. by a different game server) since the moment it was read. If the value or sort key did change, the transform function is invoked again with the most recent item value and sort key. This cycle repeats until the value and sort key are saved successfully or the transform function returns nil to abort the operation.

Parameters

Name	Type	Description
key	string	Key whose value to update.
transformFunction	Function	A function which you need to provide. The function takes the key's old value and old sort key as input and returns the new value and new sort key.
expiration	int64	Item expiration time, in seconds, after which the item will be automatically removed from the sorted map. The maximum expiration time is 45 days (3,888,000 seconds).

Returns

Type	Description
Tuple	The return value is a tuple of the last value and sort key returned by the transform function.

Field	Value
tags	["Yields"]
security	None
thread safety	Unsafe
capabilities	["DataStore"]

Code samples: View on Creator Hub (updating-sorted-map-memory-store).

Properties

Inherited from Instance

Name	Type / Returns	Description
Instance.Archivable	boolean	Determines if an `Instance` and its descendants can be cloned using `Instance:Clone()`, and can be saved/published.
Instance.archivable	boolean
Instance.Capabilities	SecurityCapabilities	The set of capabilities allowed to be used for scripts inside this container.
Instance.IsInSandbox	boolean	Indicates whether the instance is inside a sandboxed container.
Instance.Name	string	A non-unique identifier of the `Instance`.
Instance.Parent	Instance	Determines the hierarchical parent of the `Instance`.
Instance.PredictionMode	PredictionMode	Reflects the client-side prediction mode applied to the instance under server-authoritative physics.
Instance.RobloxLocked	boolean	A deprecated property that used to protect `CoreGui` objects.
Instance.Sandboxed	boolean	When enabled, the instance can only access abilities in its `Capabilities` list.
Instance.UniqueId	UniqueId	A unique identifier for the instance.

Inherited from Object

Name	Type / Returns	Description
Object.ClassName	string	A read-only string representing the class this `Object` belongs to.
Object.className	string

Events

Inherited from Instance

Name	Type / Returns	Description
Instance.AncestryChanged		Fires when the `Instance.Parent` property of this object or one of its ancestors is changed.
Instance.AttributeChanged		Fires whenever an attribute is changed on the `Instance`.
Instance.ChildAdded		Fires after an object is parented to this `Instance`.
Instance.childAdded
Instance.ChildRemoved		Fires after a child is removed from this `Instance`.
Instance.DescendantAdded		Fires after a descendant is added to the `Instance`.
Instance.DescendantRemoving		Fires immediately before a descendant of the `Instance` is removed.
Instance.Destroying		Fires immediately before (or is deferred until after) the instance is destroyed via `Instance:Destroy()`.
Instance.StyledPropertiesChanged		Fires whenever any style property is changed on the instance, including when a property is set to `nil`.

Inherited from Object

Name	Type / Returns	Description
Object.Changed		Fires immediately after a property of the object changes, with some limitations.