Module codd::expression

Defines relational algebraic expressions as generic types over Tuple types.

Structs

Builder	Is a builder for building Expression values.
Difference	Evaluates to the tuples that are in its left but not in its right sub-expressions (left - right).
Empty	Represents an empty instance containing no tuples.
Full	Is a placeholder for a "full" instance, containing all tuples of its type.
Intersect	Evaluates to all tuples that are in its both left and right sub-expressions.
Join	Represents the join of its left and right sub-expressions.
Product	Corresponds to the cartesian product of two expression.
Project	Projects the tuples of an inner sub-expression of type S to tuples of type T.
Relation	Is an expression corresponding to a relation with tuples of type T that is identified by a name.
Select	Selects tuples of the underlying sub-expression according to a given predicate.
Singleton	Represents a single tuple of type T.
Union	Evaluates to the union of the tuples in its left and right sub-expressions.
View	Represents a view in the database.

Enums

Mono	Is a recursive expression where all subexpressions act on the same Tuple type.;

Traits

Expression	Is the trait of expressions in relational algebra that can be evaluated in a database.
IntoExpression	Is the trait of types that can be turned into an Expression.
Visitor	Is the trait of objects that visit sub-expressions of an Expression. The default implementation guides the visitor through all sub-expressions of the expressions that is visited.