Microsoft Fabric Updates Blog

Announcing Eventhouse OneLake availability migration

Beginning April 9th, we will be migrating the data you have enabled for OneLake Availability in Eventhouse. During this migration, we will be backfilling all of your data along with moving it to an area of OneLake that is designated not to be charged. This allows us to simplify the billing process and provide you with the complete history of your tables.

What this means for you:

  • During the migration there will be a short period where all of your delta parquet files will not be available as we backfill the records.
  • Once completed you will have a complete copy of the table back to the length of retention set on the table.
  • You will continue to access the OneLake files in the same way and with the same performance and scale.
  • This will not have any effect on accessing the data within your Eventhouse, it will only affect the delta parquet files made available via the OneLake Availability feature.

Thank you for your understanding and cooperation as we continue to improve your experience in Microsoft Fabric!

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