Module physical_expr

Traits§

DynEq: A dyn-compatible version of Eq trait. The implementation constraints for this trait are the same as for Eq: the implementation must be reflexive, symmetric, and transitive. Additionally, if two values can be compared with DynEq and PartialEq then they must be DynEq-equal if and only if they are PartialEq-equal. It is therefore strongly discouraged to implement this trait for types that implement PartialEq<Other> or Eq<Other> for any type Other other than Self.
DynHash: A dyn-compatible version of Hash trait. If two values are equal according to DynEq, they must produce the same hash value.
PhysicalExpr: PhysicalExprs represent expressions such as A + 1 or CAST(c1 AS int).

fmt_sql: Prints a PhysicalExpr in a SQL-like format
format_physical_expr_list: Returns Display able a list of PhysicalExpr
is_dynamic_physical_expr: Check if the given PhysicalExpr is dynamic. Internally this calls snapshot_generation to check if the generation is non-zero, any dynamic PhysicalExpr should have a non-zero generation.
is_volatile: Returns true if the expression is volatile, i.e. whether it can return different results when evaluated multiple times with the same input.
snapshot_generation: Check the generation of this PhysicalExpr. Dynamic PhysicalExprs may have a generation that is incremented every time the state of the PhysicalExpr changes. If the generation changes that means this PhysicalExpr or one of its children has changed since the last time it was evaluated.
snapshot_physical_expr: Take a snapshot of the given PhysicalExpr if it is dynamic.
with_new_children_if_necessary: Returns a copy of this expr if we change any child according to the pointer comparison. The size of children must be equal to the size of PhysicalExpr::children().