optimizer

Value Members

1. object BooleanSimplification extends Rule[LogicalPlan] with PredicateHelper

   Simplifies boolean expressions: 1.

2. object ColumnPruning extends Rule[LogicalPlan]

   Attempts to eliminate the reading of unneeded columns from the query plan using the following transformations:

3. object CombineFilters extends Rule[LogicalPlan]

   Combines two adjacent Filter operators into one, merging the conditions into one conjunctive predicate.

4. object CombineLimits extends Rule[LogicalPlan]

   Combines two adjacent Limit operators into one, merging the expressions into one single expression.

5. object ConstantFolding extends Rule[LogicalPlan]

   Replaces Expressions that can be statically evaluated with equivalent Literal values.

6. object ConvertToLocalRelation extends Rule[LogicalPlan]

   Converts local operations (i.

7. object DecimalAggregates extends Rule[LogicalPlan]

   Speeds up aggregates on fixed-precision decimals by executing them on unscaled Long values.

8. object DefaultOptimizer extends Optimizer

9. object LikeSimplification extends Rule[LogicalPlan]

   Simplifies LIKE expressions that do not need full regular expressions to evaluate the condition.

10. object NullPropagation extends Rule[LogicalPlan]

    Replaces Expressions that can be statically evaluated with equivalent Literal values.

11. object OptimizeIn extends Rule[LogicalPlan]

    Replaces (value, seq[Literal]) with optimized version(value, HashSet[Literal]) which is much faster

12. object ProjectCollapsing extends Rule[LogicalPlan]

    Combines two adjacent Project operators into one and perform alias substitution, merging the expressions into one single expression.

13. object PushPredicateThroughAggregate extends Rule[LogicalPlan] with PredicateHelper

    Push Filter operators through Aggregate operators, iff the filters reference only non-aggregate attributes (typically literals or grouping expressions).

14. object PushPredicateThroughGenerate extends Rule[LogicalPlan] with PredicateHelper

    Push Filter operators through Generate operators.

15. object PushPredicateThroughJoin extends Rule[LogicalPlan] with PredicateHelper

    Pushes down Filter operators where the condition can be evaluated using only the attributes of the left or right side of a join.

16. object PushPredicateThroughProject extends Rule[LogicalPlan] with PredicateHelper

    Pushes Filter operators through Project operators, in-lining any Aliases that were defined in the projection.

17. object RemoveDispensableExpressions extends Rule[LogicalPlan]

    Removes nodes that are not necessary.

18. object RemoveLiteralFromGroupExpressions extends Rule[LogicalPlan]

    Removes literals from group expressions in Aggregate, as they have no effect to the result but only makes the grouping key bigger.

19. object ReplaceDistinctWithAggregate extends Rule[LogicalPlan]

    Replaces logical Distinct operator with an Aggregate operator.

20. object SamplePushDown extends Rule[LogicalPlan]

    Pushes operations down into a Sample.

21. object SetOperationPushDown extends Rule[LogicalPlan] with PredicateHelper

    Pushes certain operations to both sides of a Union, Intersect or Except operator.

22. object SimplifyCaseConversionExpressions extends Rule[LogicalPlan]

    Removes the inner case conversion expressions that are unnecessary because the inner conversion is overwritten by the outer one.

23. object SimplifyCasts extends Rule[LogicalPlan]

    Removes Casts that are unnecessary because the input is already the correct type.

24. object SimplifyFilters extends Rule[LogicalPlan]

    Removes filters that can be evaluated trivially.