Module join_condition_simplify 

Rules for simplifying JOIN conditions

This rule simplifies JOIN conditions, including eliminating redundant conditions and converting InnerJoin with ON true to CrossJoin.

Conversion examples

Eliminate redundant conditions

Before:

  InnerJoin ON a.id = b.id AND b.id = a.id

After:

  InnerJoin ON a.id = b.id

Convert ON true to CrossJoin

Before:

  InnerJoin ON true

After:

  CrossJoin

Applicable Conditions

JOIN conditions contain redundant expressions. JOIN condition is a constant true. JOIN conditions can be simplified.

Structs

JoinConditionSimplifyRule

Rules for simplifying JOIN conditions