Struct RelationLoader 

pub struct RelationLoader<E: QueryEngine> { /* private fields */ }

Relation loader for executing relation queries.

Implementations

impl<E: QueryEngine> RelationLoader<E>

pub fn new(engine: E) -> Self

Create a new relation loader.

pub fn with_strategy(self, strategy: RelationLoadStrategy) -> Self

Set the loading strategy.

pub fn with_batch_size(self, size: usize) -> Self

Set the batch size for separate queries.

Used by Self::build_one_to_many_queries to chunk parent IDs into bounded IN (...) lists, one statement per chunk.

pub fn engine(&self) -> &E

Get the engine.

pub fn build_one_to_many_query( &self, spec: &RelationSpec, include: &IncludeSpec, parent_ids: &[FilterValue], ) -> (String, Vec<FilterValue>)

Build a query for loading a one-to-many relation.

Placeholders and the nested Filter::to_sql call are emitted through the engine’s dialect (QueryEngine::dialect()), so the statement matches the connected backend.

pub fn build_one_to_many_queries( &self, spec: &RelationSpec, include: &IncludeSpec, parent_ids: &[FilterValue], ) -> Vec<(String, Vec<FilterValue>)>

Build one-to-many queries batched by Self::with_batch_size.

Chunks parent_ids into groups of at most batch_size and emits one statement per chunk — ceil(N / batch_size) statements — keeping each IN (...) list bounded. Callers using the separate-query strategy should execute every statement and merge the results.

pub fn build_many_to_one_query( &self, spec: &RelationSpec, child_foreign_keys: &[FilterValue], ) -> (String, Vec<FilterValue>)

Build a query for loading a many-to-one relation.

pub fn build_many_to_many_query( &self, spec: &RelationSpec, include: &IncludeSpec, parent_ids: &[FilterValue], ) -> (String, Vec<FilterValue>)

Build a query for loading a many-to-many relation.

Trait Implementations

impl<E: QueryEngine + Clone> Clone for RelationLoader<E>

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.