optimizer

Value Members

1. object BooleanSimplification extends Rule[LogicalPlan]

   Simplifies boolean expressions where the answer can be determined without evaluating both sides.

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 NullPropagation extends Rule[LogicalPlan]

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

7. object Optimizer extends RuleExecutor[LogicalPlan]

8. 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.

9. object PushPredicateThroughProject extends Rule[LogicalPlan]

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

10. object SimplifyCaseConversionExpressions extends Rule[LogicalPlan]

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

11. object SimplifyCasts extends Rule[LogicalPlan]

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

12. object SimplifyFilters extends Rule[LogicalPlan]

    Removes filters that can be evaluated trivially.