Struct TableToModel 

pub struct TableToModel { /* private fields */ }

Expression template for converting table rows into model records.

Contains one expression per model field. Each expression references table columns and produces the corresponding model field value. During lowering, these expressions construct SELECT clauses that return model-shaped data.

Examples

use toasty_core::schema::mapping::TableToModel;

let t2m: &TableToModel = &model_mapping.table_to_model;
// Get the full returning expression for SELECT
let returning = t2m.lower_returning_model();

Implementations

impl TableToModel

pub fn new(expr: ExprRecord) -> TableToModel

Creates a new TableToModel from the given expression record.

Examples

use toasty_core::schema::mapping::TableToModel;
use toasty_core::stmt::ExprRecord;

let record = ExprRecord::default();
let t2m = TableToModel::new(record);

pub fn lower_returning_model(&self) -> Expr

Returns the complete expression record for use in a RETURNING clause.

Examples

let expr = table_to_model.lower_returning_model();
// Use `expr` in a SELECT or RETURNING clause

pub fn lower_expr_reference(&self, nesting: usize, index: usize) -> Expr

Returns the expression for a single field reference.

Arguments

• nesting - The scope nesting level. Non-zero when the reference appears in a subquery relative to the table source.
• index - The field index within the model.

Examples

// Get the expression for field 0 at the top-level scope
let expr = table_to_model.lower_expr_reference(0, 0);

Trait Implementations

impl Clone for TableToModel

fn clone(&self) -> TableToModel

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TableToModel

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

Formats the value using the given formatter.

impl Default for TableToModel

fn default() -> TableToModel

Returns the “default value” for a type.