Trait PartitionExprFetcher 

pub trait PartitionExprFetcher {
    // Required method
    fn fetch_expr<'life0, 'async_trait>(
        &'life0 self,
        region_id: RegionId,
    ) -> Pin<Box<dyn Future<Output = Option<String>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait;
}

A fetcher to retrieve partition expr for a region.

Compatibility: older regions didn’t persist partition_expr in engine metadata, while newer ones do. On open, we backfill it via this fetcher and persist it to the manifest so future opens don’t need refetching.

Required Methods

fn fetch_expr<'life0, 'async_trait>( &'life0 self, region_id: RegionId, ) -> Pin<Box<dyn Future<Output = Option<String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Dyn Compatibility

This trait is dyn compatible.

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

Implementors