Microsoft Fabric Updates Blog

Open Mirroring UI enhancements and CSV support to help you get started today

Open Mirroring:

Mirroring is one of the easiest ways to get data into Fabric, it creates a copy of your data in OneLake and keeps it up to date; no ETL required. Open Mirroring empowers everyone to create their own Mirroring Source using the publicly available API that allows you to replicate data from anywhere. Open Mirroring is designed to be extensible and customizable, enabling you to seamlessly use any data in Fabric without the need for complex transformations.

Support for CSVs:

The release of support for CSV formats for Open Mirroring allows you to upload CSV files in addition to parquet files when you’re using the API or user experience. Everything will continue to work the same, simply push your CSVs (like you would a parquet file today) to the OneLake landing zone and our engine takes care of the rest. We convert the data into a delta format before pushing the data into OneLake and keeping it up to date as you load changes. Today we support CSV files with first row as header and will continue innovating and adding updates with each release.

Revamped user experience:

Our APIs are a great way for you to get stated with Open Mirroring, but sometimes you just want to test things out right in Fabric. Now you can with our revamped UX, here’s how it works:

  • Create a Mirror Database by searching for Mirror in ‘New Item’ and selecting ‘Mirror database (preview)’.
  • Add your files by selecting Upload files on the home page of the mirrored database or by dragging and dropping Parquet or CSV files.
  • On the Upload files page, upload a Parquet or CSV file using the upload dialog in the Fabric portal.

  • On the Preview data page, you can see a preview of the data you are about to upload. Provide the Table name a name and specify Primary key column(s), then select Create table.
  • Once uploaded, your data immediately starts to replicate into OneLake. After a few minutes, in the Explorer, you can view the files that have been replicated in OneLake by selecting a file from Uploaded files or a table in Tables in OneLake.
  • From the Replication status in the Explorer, you can see how many rows have been replicated and any errors associated with the data you are mirroring into OneLake.
  • If you have changed data in a Parquet or CSV format for existing tables in your mirrored database, you can upload or drag and drop these change files. The changes are automatically reflected in OneLake.

Learn more about Open Mirroring and get started today! Check out this Tutorial: Configure Microsoft Fabric open mirrored databases.

Submit your feedback on Fabric Ideas and join the conversation on the Fabric Community. To get into the technical details, head over to the Fabric documentation

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