Trait diesel::sql_types::TypeMetadata
source · pub trait TypeMetadata {
type TypeMetadata;
type MetadataLookup: ?Sized;
}
Expand description
Information about how a backend stores metadata about given SQL types
Required Associated Types§
sourcetype TypeMetadata
type TypeMetadata
The actual type used to represent metadata.
On PostgreSQL, this is the type’s OID. On MySQL and SQLite, this is an enum representing all storage classes they support.
sourcetype MetadataLookup: ?Sized
type MetadataLookup: ?Sized
The type used for runtime lookup of metadata.
For most backends, which don’t support user defined types, this will
be ()
.