[FEATURE]: Support for PostgreSQL functions.

[atiqueMorshed]

As per my understanding from the Drizzle documentations, there is no way to create or even use existing database functions.

I imagine this would be a very good addition since database functions are so powerful and handy.

[Raesta]

@atiqueMorshed The only way to do this is to create an empty migration with the Postgress declaration of your function.

[jamesarosen]

The key downside to this approach is that you end up with many copies of the function definition and no git link between them. A pull request that modifies the function shows the full new definition, but no diff from the previous version.

[jamesarosen]

According to @AlexBlokh,

[JavaScript migrations] will be implemented right after migrations v3

JavaScript migrations would let us do this. Even if snapshotting slowly-changing SQL files isn't supported out-of-the-box, we can still implement it in JS-land.

[osdiab]

I would also greatly appreciate this as for people using tools like Hasura and Postgraphile to spin up GQL APIs from Postgres databases, Postgres functions are a major way of extending the generated GraphQL schemas; without this, significant aspects that determine the GraphQL API surface area are missing in the Drizzle schema.