Prefer unique constraints over indexes on SQL Server #3018
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Unique constraint and index do not differ in SQL Server today. The problem is if we create an index and try to drop a constraint, the drop fails. Currently if the unique is added when the table is created, we add constraint. If the table is altered with a unique constraint we create an index instead. Dropping this does not work. The PR makes altering the table with an `@unique` to use constraints instead of an index. Closes: prisma/prisma#14051
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We always create constraints, but if the project has used an index, we drop an index instead of a constraint if wanting to remove it.
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Unique constraint and index do not differ in SQL Server today. The problem is if we create an index and try to drop a constraint, the drop fails.
Currently if the unique is added when the table is created, we add constraint. If the table is altered with a unique constraint we create an index instead. Dropping this does not work.
The PR makes altering the table with an
@uniqueto use constraints instead of an index.Closes: prisma/prisma#14051