Enum SelectColumns 

#[non_exhaustive]
pub enum SelectColumns {
    All,
    Columns(Vec<Column>),
    Aggregations(Vec<AggregateFunction>),
    Mixed {
        columns: Vec<Column>,
        aggregations: Vec<AggregateFunction>,
        similarity_scores: Vec<SimilarityScoreExpr>,
        qualified_wildcards: Vec<String>,
        window_functions: Vec<WindowFunction>,
    },
    SimilarityScore(SimilarityScoreExpr),
    QualifiedWildcard(String),
}

Columns in a SELECT statement.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

All

Select all columns (*).

Columns(Vec<Column>)

Select specific columns.

Aggregations(Vec<AggregateFunction>)

Select aggregate functions.

Mixed

Mixed: columns + aggregations + similarity scores + qualified wildcards + window functions.

Fields

columns: Vec<Column>

Regular columns.

aggregations: Vec<AggregateFunction>

Aggregate functions.

similarity_scores: Vec<SimilarityScoreExpr>

similarity() score expressions.

qualified_wildcards: Vec<String>

Qualified wildcards (e.g., ctx.*).

window_functions: Vec<WindowFunction>

Window function expressions (Issue #386).

SimilarityScore(SimilarityScoreExpr)

Select similarity() score only (zero-arg form).

QualifiedWildcard(String)

Select alias.* (qualified wildcard).

Implementations

impl SelectColumns

pub fn to_display_names(&self) -> Vec<String>

Returns human-readable column names for display, one per SELECT-list item in grammar order.

Used by Python/WASM bindings to expose the column-metadata contract.

Completeness

Every SELECT-list variant must contribute exactly one entry per item it contains. Historically the Mixed arm dropped similarity_scores and qualified_wildcards via a .. pattern, which silently shortened the column list for queries that combined them with regular columns — a correctness bug that was observable through Python/WASM callers reading the column count or iterating the list. That bug is now fixed; the returned list reflects the complete SELECT projection.

Compatibility note: callers that previously relied on the incomplete list (e.g. hard-coded len() == columns.len()) will now see additional entries. The new contract is pinned by ast_tests::test_display_names_mixed_includes_all_variants.

Trait Implementations

impl Clone for SelectColumns

fn clone(&self) -> SelectColumns

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SelectColumns

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for SelectColumns

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for SelectColumns

fn eq(&self, other: &SelectColumns) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for SelectColumns

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for SelectColumns