Package org.apache.flink.table.planner.hint

Enum JoinStrategy

java.lang.Object

java.lang.Enum<JoinStrategy>

org.apache.flink.table.planner.hint.JoinStrategy

All Implemented Interfaces:

Serializable, Comparable<JoinStrategy>

public enum JoinStrategy
extends Enum<JoinStrategy>

Currently available join strategies and corresponding join hint names.

Enum Constant Summary

Enum Constants

Enum Constant	Description
BROADCAST	Instructs the optimizer to use broadcast hash join strategy.
LOOKUP	Instructs the optimizer to use lookup join strategy.
NEST_LOOP	Instructs the optimizer to use nest loop join strategy.
SHUFFLE_HASH	Instructs the optimizer to use shuffle hash join strategy.
SHUFFLE_MERGE	Instructs the optimizer to use shuffle sort merge join strategy.

Method Summary

Modifier and Type	Method	Description
String	getJoinHintName()
static boolean	isJoinStrategy(String hintName)
static boolean	isLookupHint(String hintName)
static boolean	validOptions(String hintName, List<String> options)
static JoinStrategy	valueOf(String name)	Returns the enum constant of this type with the specified name.
static JoinStrategy[]	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

BROADCAST

public static final JoinStrategy BROADCAST

Instructs the optimizer to use broadcast hash join strategy. If both sides are specified in this hint, the side that is first written will be broadcast.

SHUFFLE_HASH

public static final JoinStrategy SHUFFLE_HASH

Instructs the optimizer to use shuffle hash join strategy. If both sides are specified in this hint, the side that is first written will be treated as the build side.

SHUFFLE_MERGE

public static final JoinStrategy SHUFFLE_MERGE

Instructs the optimizer to use shuffle sort merge join strategy. As long as one of the side is specified in this hint, it will be tried.

NEST_LOOP

public static final JoinStrategy NEST_LOOP

Instructs the optimizer to use nest loop join strategy. If both sides are specified in this hint, the side that is first written will be treated as the build side.

LOOKUP

public static final JoinStrategy LOOKUP

Instructs the optimizer to use lookup join strategy. Only accept key-value hint options.

Method Detail

values

public static JoinStrategy[] 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 (JoinStrategy c : JoinStrategy.values())
    System.out.println(c);

Returns:

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

valueOf

public static JoinStrategy 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

isJoinStrategy

public static boolean isJoinStrategy(String hintName)

getJoinHintName

public String getJoinHintName()

validOptions

public static boolean validOptions(String hintName,
                                   List<String> options)

isLookupHint

public static boolean isLookupHint(String hintName)