planning

abstract class GenericStrategy[PhysicalPlan <: TreeNode[PhysicalPlan]] extends Logging

Given a LogicalPlan, returns a list of PhysicalPlans that can be used for execution.
Given a LogicalPlan, returns a list of PhysicalPlans that can be used for execution. If this strategy does not apply to the give logical operation then an empty list should be returned.
abstract class QueryPlanner[PhysicalPlan <: TreeNode[PhysicalPlan]] extends AnyRef

Abstract class for transforming LogicalPlans into physical plans.
Abstract class for transforming LogicalPlans into physical plans. Child classes are responsible for specifying a list of Strategy objects that each of which can return a list of possible physical plan options. If a given strategy is unable to plan all of the remaining operators in the tree, it can call planLater, which returns a placeholder object that will be filled in using other available strategies.
TODO: RIGHT NOW ONLY ONE PLAN IS RETURNED EVER... PLAN SPACE EXPLORATION WILL BE IMPLEMENTED LATER.
PhysicalPlan
The type of physical plan produced by this QueryPlanner

object ExtractEquiJoinKeys extends Logging with PredicateHelper

A pattern that finds joins with equality conditions that can be evaluated using equi-join.
A pattern that finds joins with equality conditions that can be evaluated using equi-join.
Null-safe equality will be transformed into equality as joining key (replace null with default value).
object PhysicalOperation extends PredicateHelper

A pattern that matches any number of project or filter operations on top of another relational operator.
A pattern that matches any number of project or filter operations on top of another relational operator. All filter operators are collected and their conditions are broken up and returned together with the top project operator. Aliases are in-lined/substituted if necessary.
object Unions

A pattern that collects all adjacent unions and returns their children as a Seq.