CoalesceBucketsInJoin Physical Optimization¶
CoalesceBucketsInJoin is a physical query optimization (aka physical query preparation rule or simply preparation rule).
CollapseCodegenStages is a Catalyst rule for transforming physical query plans (
CoalesceBucketsInJoin is part of the preparations batch of physical query plan rules and is executed when
QueryExecution is requested for the optimized physical query plan (in executedPlan phase of a query execution).
CoalesceBucketsInJoin uses the spark.sql.bucketing.coalesceBucketsInJoin.enabled configuration property.
apply( plan: SparkPlan): SparkPlan
apply is part of the Rule abstraction.
apply is a noop with the spark.sql.bucketing.coalesceBucketsInJoin.enabled configuration property turned off.
apply uses ExtractJoinWithBuckets to match on BaseJoinExec physical operators.