A deploy request can fail while copying a table because existing rows do not satisfy a unique key in the new schema.
PlanetScale copies the table in the background and inserts existing rows into a new table that uses the deployed schema. If that schema adds a UNIQUE key, or changes the primary key, and two existing rows have the same value for those columns, the second insert is rejected:
The first quoted value is one of the duplicates. The key name tells you which columns are in conflict. The key name may be shown with a _vt_vrp_... prefix, which is the name of the table being copied into.
How to fix it
Find the rows that share a value for the columns in the key, then remove or change them so each combination is unique:
Then retry the failed tables. Retrying before every duplicate is resolved will cause another failure.
If the duplicates are expected, change the key on your branch so it is no longer unique, or add a column to it that makes each row distinct, and open a new deploy request.
The copy runs while your application keeps writing to the table. If the application inserts a duplicate during the copy, the deploy fails with the same error. Make sure new writes also satisfy the unique key before retrying.
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