org.apache.hadoop.hive.ql.optimizer

Enum SharedWorkOptimizer.Mode

java.lang.Object

java.lang.Enum<SharedWorkOptimizer.Mode>

org.apache.hadoop.hive.ql.optimizer.SharedWorkOptimizer.Mode

All Implemented Interfaces:

Serializable, Comparable<SharedWorkOptimizer.Mode>

Enclosing class:

SharedWorkOptimizer

public static enum SharedWorkOptimizer.Mode
extends Enum<SharedWorkOptimizer.Mode>

SharedWorkOptimization strategy modes

Enum Constant Summary

Enum Constants

Enum Constant and Description
DPPUnion Fuses two filtered table scans into a single one.
RemoveSemijoin Merges a filtered scan into a non-filtered scan.
SubtreeMerge Merges two identical subtrees.

Method Summary

Modifier and Type	Method and Description
static SharedWorkOptimizer.Mode	valueOf(String name) Returns the enum constant of this type with the specified name.
static SharedWorkOptimizer.Mode[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

SubtreeMerge

public static final SharedWorkOptimizer.Mode SubtreeMerge

Merges two identical subtrees.

RemoveSemijoin

public static final SharedWorkOptimizer.Mode RemoveSemijoin

Merges a filtered scan into a non-filtered scan. In case we are already scanning the whole table - we should not scan it twice.

DPPUnion

public static final SharedWorkOptimizer.Mode DPPUnion

Fuses two filtered table scans into a single one. Dynamic filter subtree is kept on both sides - but the table is onlt scanned once.

Method Detail

values

public static SharedWorkOptimizer.Mode[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (SharedWorkOptimizer.Mode c : SharedWorkOptimizer.Mode.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static SharedWorkOptimizer.Mode valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null