Struct InferredPredicates 

struct InferredPredicates {
    predicates: Vec<Expr>,
    is_inner_join: bool,
}

Inferred predicates collector. When the JoinType is not Inner, we need to detect whether the inferred predicate can strictly filter out NULL, otherwise ignore it. e.g.

SELECT * FROM t1 LEFT JOIN t2 ON t1.c0 = t2.c0 WHERE t2.c0 IS NULL;

We cannot infer the predicate t1.c0 IS NULL, otherwise the predicate will be pushed down to the left side, resulting in the wrong result.

Fields

predicates: Vec<Expr>

is_inner_join: bool

Implementations

impl InferredPredicates

fn new(join_type: JoinType) -> Self

fn try_build_predicate( &mut self, predicate: Expr, replace_map: &HashMap<&Column, &Column>, ) -> Result<()>