Trait Migrates 

pub trait Migrates: RelationalBackend {
    // Required methods
    fn migrate(
        &self,
        migrations: &[Migration],
    ) -> impl Future<Output = Result<MigrateReport, MigrateError>> + Send;
    fn applied_versions(
        &self,
    ) -> impl Future<Output = Result<Vec<i64>, MigrateError>> + Send;
}

A relational backend that keeps a migration ledger.

The ledger lives in the connection’s current schema (or database): point this at a database a program owns, never at one whose ledger belongs to something else.

Required Methods

fn migrate( &self, migrations: &[Migration], ) -> impl Future<Output = Result<MigrateReport, MigrateError>> + Send

Apply migrations in version order, skipping those already applied. Each migration runs in its own transaction where the database can; refuses (applying nothing further) if an applied migration’s text has changed, if the database has applied a version the program does not know, or if a migration is recorded as dirty.

fn applied_versions( &self, ) -> impl Future<Output = Result<Vec<i64>, MigrateError>> + Send

The versions the ledger says succeeded, ascending; empty if there is no ledger yet.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl<R: RelationalBackend> Migrates for Defective<'_, R>

The known-bad migrator: no ledger, no checksum, no transaction. It runs each migration’s statements (split on ;) straight on the wrapped backend every time it is asked.