org.apache.flink.table.planner.hint

Class FlinkHints

java.lang.Object

org.apache.flink.table.planner.hint.FlinkHints

public abstract class FlinkHints
extends Object

Utility class for Flink hints.

Field Summary

Fields

Modifier and Type	Field and Description
static String	HINT_ALIAS
static String	HINT_NAME_JSON_AGGREGATE_WRAPPED Internal hint that JSON aggregation function arguments have been wrapped already.
static String	HINT_NAME_OPTIONS

Constructor Summary

Constructors

Constructor and Description
FlinkHints()

Method Summary

Modifier and Type	Method and Description
static boolean	canTransposeToTableScan(org.apache.calcite.rel.RelNode node)
static org.apache.calcite.rel.RelNode	capitalizeJoinHints(org.apache.calcite.rel.RelNode root)
static org.apache.calcite.rel.RelNode	clearJoinHintsOnUnmatchedNodes(org.apache.calcite.rel.RelNode root) Clear the join hints on some nodes where these hints should not be attached.
static List<org.apache.calcite.rel.hint.RelHint>	getAllJoinHints(List<org.apache.calcite.rel.hint.RelHint> allHints) Get all join hints.
static Map<String,String>	getHintedOptions(List<org.apache.calcite.rel.hint.RelHint> tableHints) Returns the OPTIONS hint options from the given list of table hints tableHints, never null.
static List<org.apache.calcite.rel.hint.RelHint>	getQueryBlockAliasHints(List<org.apache.calcite.rel.hint.RelHint> allHints) Get all query block alias hints.
static Optional<String>	getTableAlias(org.apache.calcite.rel.RelNode node)
static Optional<String>	getTableName(org.apache.calcite.plan.RelOptTable table) Returns the qualified name of a table scan, otherwise returns empty.
static Map<String,String>	mergeTableOptions(Map<String,String> hints, Map<String,String> props) Merges the dynamic table options from hints and static table options from table definition props.
static org.apache.calcite.rel.RelNode	resolveSubQuery(org.apache.calcite.rel.RelNode node, Function<org.apache.calcite.rel.RelNode,org.apache.calcite.rel.RelNode> resolver) Resolve the RelNode of the sub query in the node and return a new node.
static String	stringifyHints(List<org.apache.calcite.rel.hint.RelHint> hints)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

HINT_NAME_OPTIONS

public static final String HINT_NAME_OPTIONS

See Also:

Constant Field Values

HINT_ALIAS

public static final String HINT_ALIAS

See Also:

Constant Field Values

HINT_NAME_JSON_AGGREGATE_WRAPPED

public static final String HINT_NAME_JSON_AGGREGATE_WRAPPED

Internal hint that JSON aggregation function arguments have been wrapped already. See WrapJsonAggFunctionArgumentsRule.

See Also:

Constant Field Values

Constructor Detail

FlinkHints

public FlinkHints()

Method Detail

getHintedOptions

public static Map<String,String> getHintedOptions(List<org.apache.calcite.rel.hint.RelHint> tableHints)

Returns the OPTIONS hint options from the given list of table hints tableHints, never null.

mergeTableOptions

public static Map<String,String> mergeTableOptions(Map<String,String> hints,
                                                   Map<String,String> props)

Merges the dynamic table options from hints and static table options from table definition props.

The options in hints would override the ones in props if they have the same option key.

Parameters:

hints - Dynamic table options, usually from the OPTIONS hint

props - Static table options defined in DDL or connect API

Returns:

New options with merged dynamic table options, or the old props if there is no dynamic table options

getTableAlias

public static Optional<String> getTableAlias(org.apache.calcite.rel.RelNode node)

canTransposeToTableScan

public static boolean canTransposeToTableScan(org.apache.calcite.rel.RelNode node)

getTableName

public static Optional<String> getTableName(org.apache.calcite.plan.RelOptTable table)

Returns the qualified name of a table scan, otherwise returns empty.

stringifyHints

public static String stringifyHints(List<org.apache.calcite.rel.hint.RelHint> hints)

getAllJoinHints

public static List<org.apache.calcite.rel.hint.RelHint> getAllJoinHints(List<org.apache.calcite.rel.hint.RelHint> allHints)

Get all join hints.

getQueryBlockAliasHints

public static List<org.apache.calcite.rel.hint.RelHint> getQueryBlockAliasHints(List<org.apache.calcite.rel.hint.RelHint> allHints)

Get all query block alias hints.

Because query block alias hints will be propagated from root to leaves, so maybe one node will contain multi alias hints. But only the first one is the real query block name where this node is.

capitalizeJoinHints

public static org.apache.calcite.rel.RelNode capitalizeJoinHints(org.apache.calcite.rel.RelNode root)

resolveSubQuery

public static org.apache.calcite.rel.RelNode resolveSubQuery(org.apache.calcite.rel.RelNode node,
                                                             Function<org.apache.calcite.rel.RelNode,org.apache.calcite.rel.RelNode> resolver)

Resolve the RelNode of the sub query in the node and return a new node.

clearJoinHintsOnUnmatchedNodes

public static org.apache.calcite.rel.RelNode clearJoinHintsOnUnmatchedNodes(org.apache.calcite.rel.RelNode root)

Clear the join hints on some nodes where these hints should not be attached.