icydb-core 0.213.35

IcyDB — A schema-first typed query engine and persistence runtime for Internet Computer canisters
Documentation 
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//! Module: db::query::plan::order_term
//! Responsibility: canonical index-order term rendering shared by planner boundaries.
//! Does not own: query expression parsing or executor slot resolution.
//! Boundary: keeps index-key canonicalization in one place.

use crate::db::access::{SemanticIndexKeyItemRef, SemanticIndexKeyItemsRef};

/// Return one canonical ORDER BY term list from reduced index key-item facts.
#[must_use]
pub(in crate::db) fn index_key_item_order_terms(
    key_items: SemanticIndexKeyItemsRef<'_>,
) -> Vec<String> {
    match key_items {
        SemanticIndexKeyItemsRef::Fields(fields) => fields.to_vec(),
        SemanticIndexKeyItemsRef::Accepted(items) => {
            canonical_index_order_terms(items.iter().map(|item| item.as_ref()))
        }
    }
}

// Field-only indexes and mixed key-item indexes share the same canonical
// ORDER BY rendering contract; only the source iterator for key items differs.
fn canonical_index_order_terms<'a, I>(key_items: I) -> Vec<String>
where
    I: IntoIterator<Item = SemanticIndexKeyItemRef<'a>>,
{
    key_items
        .into_iter()
        .map(SemanticIndexKeyItemRef::canonical_text)
        .collect()
}