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DatabaseBackend

umbral_core::backend

Trait DatabaseBackend 

Source 
pub trait DatabaseBackend:
    Debug
    + Send
    + Sync
    + 'static {
    // Required methods
    fn name(&self) -> &'static str;
    fn supports(&self, feature: BackendFeature) -> bool;
    fn map_type(&self, ty: SqlType) -> ColumnType;

    // Provided method
    fn map_column(&self, col: &Column) -> ColumnType { ... }
}
Expand description

One umbral-supported relational backend.

Trait surface kept narrow at M4: identity (name), feature queries (supports), and SQL-type mapping for the migration engine (map_type). quote_identifier, render_upsert, and dialect- specific rendering helpers get added when M5’s migration engine and bulk-insert paths need them; sea-query exposes those via per-backend QueryBuilder types rather than a single dialect enum, so umbral dispatches through name() for now and adds typed rendering helpers when there’s a real consumer.

Required Methods§

Source

fn name(&self) -> &'static str

Stable string identifier. "postgres", "sqlite", etc. Used as the matching key in FieldSpec::supported_backends, and shown in system-check error messages.

Source

fn supports(&self, feature: BackendFeature) -> bool

Whether this backend supports the given feature. Used by the system check to gate Postgres-only field types (Array, HStore, jsonb) and by the migration engine to choose between INSERT ... RETURNING and INSERT; last_insert_rowid().

Source

fn map_type(&self, ty: SqlType) -> ColumnType

Map an umbral SqlType to the sea-query ColumnType that renders the right native SQL column type on this backend. The migration engine (M5) reads this when generating CREATE TABLE.

Provided Methods§

Source

fn map_column(&self, col: &Column) -> ColumnType

Map a full column (type + per-column hints like max_length) to its sea-query ColumnType. Default impl delegates to map_type — backends that want to lift hints (Postgres rendering Text + max_length=N as VARCHAR(N), for example) override this. The migration engine prefers this over map_type so the per-column attributes flow into DDL.

Dyn Compatibility§

This trait is dyn compatible.

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

Implementors§