Support GiST Index type with Postgres

Problem

I’m trying to use Prisma with geographic data in PostGIS. There’s an issue to track actual PostGIS support (#1798) but this is a narrower concern - the support of GiST indexes. These were mentioned when index type support was introduced (#10080), but only BTree or Hash were implemented.

Suggested solution

Allow GiST as an option to the type parameter for an index.

Alternatives

This could be hacked in with an arbitrary migration, but that is not a clean solution.

[janpio]

This is now available in our dev version, so you can use prisma@dev and the extendedIndexes preview feature if you want to play with it. Optimally start with a db pull on your existing database that uses these, and see if they are added correctly to the introspected schema. Afterwards you can also play with adding additional ones and then migrate (with db push or migrate dev).

Let us know how it goes please!

[tmcw]

Oh! Yeah - that’s because there are use cases (like mine) in which GiST index support alone would be enough to make Prisma usable without hacks. We can already specify geometry columns, but can’t load data into them until they have the right index type.