# getSnapshotMsgId {#getsnapshotmsgid}

**Parent topic:**[Functions](../../Functions/category.md)

## Syntax {#syntax}

`getSnapshotMsgId(engine)`

## Arguments {#arguments}

**engine** is a built-in streaming engine, i.e., the abstract table object return by functions such as [createReactiveStateEngine](../c/createReactiveStateEngine.md).

## Details {#details}

Get the message ID \(msgId\) of the last snapshot of the specified streaming engine when resubscibing after an interruption of subscription. If snapshot is enabled, during resubscription the parameter *offset* of function [subscribeTable](../s/subscribeTable.md) is set to `getSnapshotMsgId(engine)+1`. The streaming engine will load the snapshot and start to subcribe from the next message after `getSnapshotMsgId(engine)`.

