Package org.apache.iotdb.db.mpp.plan.analyze

Class GroupByLevelController

java.lang.Object

org.apache.iotdb.db.mpp.plan.analyze.GroupByLevelController

public class GroupByLevelController
extends java.lang.Object

This class is used to control the row number of group by level query. For example, selected series[root.sg.d1.s1, root.sg.d2.s1, root.sg2.d1.s1], level = 1; the result rows will be [root.sg.*.s1, root.sg2.*.s1], sLimit and sOffset will be used to control the result numbers rather than the selected series.

Constructor Summary

Constructors

Constructor	Description
GroupByLevelController(int[] levels, TypeProvider typeProvider)

Method Summary

Modifier and Type	Method	Description
void	control(boolean isCountStar, Expression expression, java.lang.String alias)
org.apache.iotdb.commons.path.PartialPath	generatePartialPathByLevel(boolean isCountStar, org.apache.iotdb.commons.path.PartialPath rawPath, int[] pathLevels)	Transform an originalPath to a partial path that satisfies given level.
java.lang.String	getAlias(java.lang.String columnName)
java.util.Map<Expression,java.util.Set<Expression>>	getGroupedPathMap()
java.util.Map<Expression,Expression>	getRawPathToGroupedPathMap()

Methods inherited from class java.lang.Object

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

Constructor Detail

GroupByLevelController

public GroupByLevelController(int[] levels,
                              TypeProvider typeProvider)

Method Detail

control

public void control(boolean isCountStar,
                    Expression expression,
                    java.lang.String alias)

generatePartialPathByLevel

public org.apache.iotdb.commons.path.PartialPath generatePartialPathByLevel(boolean isCountStar,
                                                                            org.apache.iotdb.commons.path.PartialPath rawPath,
                                                                            int[] pathLevels)

Transform an originalPath to a partial path that satisfies given level. Path nodes don't satisfy the given level will be replaced by "*" except the sensor level, e.g. generatePartialPathByLevel("root.sg.dh.d1.s1", 2) will return "root.*.dh.*.s1".

Especially, if count(*), then the sensor level will be replaced by "*" too.

Returns:

result partial path

getGroupedPathMap

public java.util.Map<Expression,java.util.Set<Expression>> getGroupedPathMap()

getAlias

public java.lang.String getAlias(java.lang.String columnName)

getRawPathToGroupedPathMap

public java.util.Map<Expression,Expression> getRawPathToGroupedPathMap()