Enum RelExpr

pub enum RelExpr {
    RelVar(Arc<TableSchema>, TyId),
    Select(Box<Select>),
    Proj(Box<Project>),
    Join(Box<[RelExpr]>, TyId),
    Union(Box<RelExpr>, Box<RelExpr>),
    Minus(Box<RelExpr>, Box<RelExpr>),
    Dedup(Box<RelExpr>),
}

A logical relational expression

Variants

RelVar(Arc<TableSchema>, TyId)

A base table

Select(Box<Select>)

A filter

Proj(Box<Project>)

A projection

Join(Box<[RelExpr]>, TyId)

An n-ary join

Union(Box<RelExpr>, Box<RelExpr>)

Bag union

Minus(Box<RelExpr>, Box<RelExpr>)

Bag difference

Dedup(Box<RelExpr>)

Bag -> set

Implementations

impl RelExpr

pub fn project(input: RelExpr, expr: Let) -> Self

Instantiate a projection RelExpr::Proj

pub fn select(input: RelExpr, expr: Let) -> Self

Instantiate a selection RelExpr::Select

pub fn ty_id(&self) -> TyId

The type id of this relation expression

pub fn ty<'a>(&self, ctx: &'a TyCtx) -> Result<TypeWithCtx<'a>, InvalidTypeId>

The type of this relation expression

pub fn table_id(&self, ctx: &mut TyCtx) -> Result<TableId, TypingError>

Trait Implementations

impl Debug for RelExpr

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

Formats the value using the given formatter.