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How to Prevent Duplicate Entries to enter to delta lake of Azure Storage?

User16790091296
Contributor II

I Have a Dataframe stored in the format of delta into Adls, now when im trying to append new updated rows to that delta lake it should, Is there any way where i can delete the old existing record in delta and add the new updated Record.

There is a unique Column for the schema of DataFrame stored in Delta. by which we can check whether the record is updated or new.

1 REPLY 1

Ryan_Chynoweth
Esteemed Contributor

To achieve this you should use a merge command that will update rows that are existing with the unique ID. This will update the rows that already exist and insert the rows that do not.

If you want to do it manually, you could delete rows using the DELETE command then do an insert of all the new rows. This is not recommended as it is less performant than a merge.

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