Struct SelectBuilder 

pub struct SelectBuilder { /* private fields */ }

Available on crate feature unparser only.

Implementations

impl SelectBuilder

pub fn next_flatten_alias(&mut self) -> String

Generate a unique alias for a LATERAL FLATTEN relation (_unnest_1, _unnest_2, …). Each call returns a fresh name.

pub fn add_flatten_table_alias(&mut self, alias: String)

Register a table alias as pointing to a LATERAL FLATTEN relation.

pub fn flatten_table_aliases_empty(&self) -> bool

Returns true if no FLATTEN table aliases have been registered.

pub fn is_flatten_table_alias(&self, alias: &str) -> bool

Returns true if the given table alias refers to a FLATTEN relation.

pub fn current_flatten_alias(&self) -> Option<String>

Returns the most recently generated flatten alias, or None if next_flatten_alias has not been called yet.

pub fn distinct(&mut self, value: Option<Distinct>) -> &mut Self

pub fn top(&mut self, value: Option<Top>) -> &mut Self

pub fn projection(&mut self, value: Vec<SelectItem>) -> &mut Self

pub fn pop_projections(&mut self) -> Vec<SelectItem>

pub fn already_projected(&self) -> bool

Returns true if a projection has been explicitly set via projection().

This method is used to determine whether the SELECT clause has already been defined, which helps avoid creating duplicate projection nodes during query unparsing. It returns true for both empty and non-empty projections.

Returns

• true if projection() has been called (regardless of whether it was empty or not)
• false if no projection has been set yet

Example

let mut builder = SelectBuilder::default();
assert!(!builder.already_projected());

builder.projection(vec![]);
assert!(builder.already_projected()); // true even for empty projection

builder.projection(vec![SelectItem::Wildcard(...)]);
assert!(builder.already_projected()); // true for non-empty projection

pub fn into(&mut self, value: Option<SelectInto>) -> &mut Self

pub fn from(&mut self, value: Vec<TableWithJoinsBuilder>) -> &mut Self

pub fn push_from(&mut self, value: TableWithJoinsBuilder) -> &mut Self

pub fn pop_from(&mut self) -> Option<TableWithJoinsBuilder>

pub fn lateral_views(&mut self, value: Vec<LateralView>) -> &mut Self

pub fn replace_mark(&mut self, existing_expr: &Expr, value: &Expr) -> &mut Self

Replaces the selection with a new value.

This function is used to replace a specific expression within the selection. Unlike the selection method which combines existing and new selections with AND, this method searches for and replaces occurrences of a specific expression.

This method is primarily used to modify LEFT MARK JOIN expressions. When processing a LEFT MARK JOIN, we need to replace the placeholder expression with the actual join condition in the selection clause.

Arguments

• existing_expr - The expression to replace
• value - The new expression to set as the selection

pub fn selection(&mut self, value: Option<Expr>) -> &mut Self

pub fn group_by(&mut self, value: GroupByExpr) -> &mut Self

pub fn cluster_by(&mut self, value: Vec<Expr>) -> &mut Self

pub fn distribute_by(&mut self, value: Vec<Expr>) -> &mut Self

pub fn sort_by(&mut self, value: Vec<OrderByExpr>) -> &mut Self

pub fn having(&mut self, value: Option<Expr>) -> &mut Self

pub fn named_window(&mut self, value: Vec<NamedWindowDefinition>) -> &mut Self

pub fn qualify(&mut self, value: Option<Expr>) -> &mut Self

pub fn value_table_mode(&mut self, value: Option<ValueTableMode>) -> &mut Self

pub fn build(&self) -> Result<Select, BuilderError>

Trait Implementations

impl Clone for SelectBuilder

fn clone(&self) -> SelectBuilder

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Default for SelectBuilder

fn default() -> Self

Returns the “default value” for a type.