Snapshot in Azure Data Lake (Dynamics 365 / CDS) – Azure Synapse Link

In the previous post, we saw how to export CDS data to Azure Data Lake Gen 2

https://nishantrana.me/2020/09/07/export-data-from-common-data-service-to-azure-data-lake-storage-gen2/

Here let us have a look how the sync and snapshot work.

We have already done the configuration and have synced the Account and Contact entity.

As the diagram depicts – there is initial sync followed by incremental writes for both entity data and metadata.

Below we can see we had initial sync completed for both contact and account entity, followed by an update in contact record which triggered another incremental sync – last synchronized on.

Within our storage container, we can see a folder created for each of the entities selected for sync.

As a part of initial sync or export, the entity data is written in CSV files

Changes in CDS are pushed to the CSV files continuously. (create, update and delete) along with a snapshot.

Within the Snapshot folder, we can see the snapshot added if there any change in the entity’s data.

Here for an account, we had no change.

Now let us look at the contact entity, here we can see the update in the 2020.csv file.

Let us look at the snapshot generated for contact; it shows no update as we have checked it within a 1-hour window of the update.

Snapshot is a read-only copy of data, which is updated at regular interval i.e. 1 hour, this ensures that the user is looking at a data which is not constantly getting refreshed.