Module mz_transform::analysis::equivalences

An analysis that reports all known-equivalent expressions for each relation.

Expressions are equivalent at a relation if they are certain to evaluate to the same Datum for all records in the relation.

Equivalences are recorded in an EquivalenceClasses, which lists all known equivalences classes, each a list of equivalent expressions.

Structs

• EQLattice 🔒
• EquivalenceClasses
  A compact representation of classes of expressions that must be equivalent.
• Equivalences
  Pulls up and pushes down predicate information represented as equivalences

Traits

• ExpressionReducer
  A type capable of simplifying MirScalarExprs.
• UnionFind 🔒

Functions

• aggregate_is_input 🔒
  True iff the aggregate function returns an input datum.