jhchee commented on issue #7554:
URL: https://github.com/apache/iceberg/issues/7554#issuecomment-1538358229

   @saimigo Merge into command is executed based on certain condition. A common 
use case is to use it for `UPSERT` operation. E.g. 
   ```sql
   MERGE INTO target t   -- a target table
   USING source s        -- your source (can be a table)
   ON t.id = s.id                -- condition to find updates for target rows 
(can be your unique identifiers)
   WHEN MATCHED UPDATE *
   WHEN NOT MATCHED INSERT *
   ```
   To address few questions, 
   1. You don't have to delete the table.
   2. Be in mind, Spark engine will perform join based on condition you define. 
This means it requires to read from a table to find the matching row, so the 
target table must exist in the first place. 


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: [email protected]

For queries about this service, please contact Infrastructure at:
[email protected]


---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to