PrismaP
Prisma•3mo ago•
1 reply
Postie

Migration adds creation of foreign key that already exists

On a MySql database there is a Download table that has this definition of a foreign key (removed columns for reading purposes):

create table Download
(
    id        int auto_increment primary key,
    saleId    int not null,
    constraint Download_saleId_fkey
        foreign key (saleId) references Sale (id)
            on update cascade on delete cascade
);

This table already has a definition in the 
schema.prisma
 file and has been migrated earlier. So the foreign key is already defined and it exists.

When I update the 
schema.prisma
 file with new models but no change in the definition of the Download model, the migration creates a line to add the foreign key to the Download table:
-- AddForeignKey
ALTER TABLE `Download` ADD CONSTRAINT `Download_saleId_fkey` FOREIGN KEY (`saleId`) REFERENCES `Sale`(`id`) ON DELETE CASCADE ON UPDATE CASCADE;


So what I did was running it with 
--create-only
 , manually delete this line and then deploy the database. However, this could happen again in upcoming migrations and I was wondering if this can be fixed. So any ideas where I should look?

Version used for Prisma "prisma": "6.18.0".
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