Struct Mapping 

pub struct Mapping {
    pub models: IndexMap<ModelId, Model>,
    pub document_columns: IndexMap<ColumnId, Type>,
}

Defines the correspondence between app-level models and database-level tables.

The mapping is constructed during schema building and remains immutable at runtime. It provides the translation layer that enables the query engine to convert model-oriented statements into table-oriented statements during the lowering phase.

Examples

use toasty_core::schema::mapping::Mapping;
use indexmap::IndexMap;

let mapping = Mapping { models: IndexMap::new() };
assert_eq!(mapping.models.len(), 0);

Fields

models: IndexMap<ModelId, Model>

Per-model mappings indexed by model identifier.

document_columns: IndexMap<ColumnId, Type>

The app-level type of each #[document] column.

A document column’s db::Column is typed by the structural stmt::Type::Object — the column does not know which embedded model it stores. That knowledge normally travels inside the mapping’s cast expressions (model_to_table carries the lowering cast, table_to_model the raising cast); this index covers the operations that bypass those templates — an Append assignment’s operand cast during statement lowering.

Implementations

impl Mapping

pub fn model(&self, id: impl Into<ModelId>) -> &Model

Returns the mapping for the specified model.

Panics

Panics if the model ID does not exist in the mapping.

Examples

let model_mapping = mapping.model(model_id);
println!("table: {:?}", model_mapping.table);

pub fn model_mut(&mut self, id: impl Into<ModelId>) -> &mut Model

Returns a mutable reference to the mapping for the specified model.

Panics

Panics if the model ID does not exist in the mapping.

Examples

let model_mapping = mapping.model_mut(model_id);
// modify fields, columns, etc.

pub fn document_column_ty(&self, id: impl Into<ColumnId>) -> Option<&Type>

Returns the app-level type of a #[document] column — Type::Model for a bare embed, List(Model) for an embed collection — or None if the column does not store a document.

Trait Implementations

impl Clone for Mapping

fn clone(&self) -> Mapping

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Mapping

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.