org.apache.lens.cube.parse

Class StorageCandidate

java.lang.Object

org.apache.lens.cube.parse.StorageCandidate

All Implemented Interfaces:

Named, Candidate, CandidateTable

public class StorageCandidate
extends Object
implements Candidate, CandidateTable

Represents a fact on a storage table and the dimensions it needs to be joined with to answer the query

Constructor Summary

Constructors

Constructor and Description
StorageCandidate(CubeInterface cube, FactTable fact, String storageName, CubeQueryContext cubeQueryContext)
StorageCandidate(StorageCandidate sc)

Method Summary

Modifier and Type	Method and Description
void	addAnswerableMeasurePhraseIndices(int index) Add `index` as answerable index in a pre-decided list of queried phrases.
boolean	contains(Candidate candidate) Returns true if this candidate contains the given candidate
StorageCandidate	copy() Clones this candidate
Set<Integer>	decideMeasurePhrasesToAnswer(Set<Integer> measureIndices)
boolean	equals(Object obj)
boolean	evaluateCompleteness(TimeRange timeRange, TimeRange queriedTimeRange, boolean failOnPartialData) Calculates if this candidate can answer the query for given time range based on actual data registered with the underlying candidate storages.
Candidate	explode() Explode this candidate into another candidate.
String	getAliasForTable(String alias)
Set<Integer>	getAnswerableMeasurePhraseIndices() Gets the index positions of answerable measure phrases in CubeQueryContext#selectPhrases
AbstractCubeTable	getBaseTable() Get base table of the candidate table
Collection<Candidate>	getChildren() Returns child candidates of this candidate if any.
Optional<Date>	getColumnEndTime(String column) This method should give end time of a column, if there's any.
Collection<String>	getColumns() Returns all the fact columns
Optional<Date>	getColumnStartTime(String column) This method should give start time of a column, if there's any.
OptionalDouble	getCost()
CubeInterface	getCube() Utility method to return cube of its cube query context
CubeQueryContext	getCubeQueryContext() A candidate always works along with its cube query context.
Map<String,Map<String,Float>>	getDataCompletenessMap() This map holds Tags (A tag refers to one or more measures) that have incomplete (below configured threshold) data.
Date	getEndTime() End Time for this candidate (calculated based on schema)
FactTable	getFact() Participating fact, storage and dimensions for this StorageCandidate
String	getFromString()
String	getName() Name of this storage candidate = storageName_factName
Set<String>	getNonExistingPartitions() Non existing partitions
int	getNumQueriedParts()
Set<FactPartition>	getParticipatingPartitions() Returns the set of fact partitions that will participate in this candidate.
TreeSet<UpdatePeriod>	getParticipatingUpdatePeriods() These are the update periods that finally participate in partitions.
Set<Dimension>	getQueriedDims()
Map<TimeRange,String>	getRangeToExtraWhereFallBack()
Map<TimeRange,Set<FactPartition>>	getRangeToPartitions()
String	getResolvedName()
Date	getStartTime() Start Time for this candidate (calculated based on schema)
String	getStorageName()
String	getStorageString(String alias) Get storage string of the base table alias passed
String	getStorageTable() Get storage table corresponding to this candidate
AbstractCubeTable	getTable() Get candidate table
Map<String,CandidateTablePruneCause.SkipUpdatePeriodCode>	getUpdatePeriodRejectionCause()
TreeSet<UpdatePeriod>	getValidUpdatePeriods() Valid update periods populated by Phase 1.
int	hashCode()
boolean	isDimAttributeEvaluable(String dim) Checks whether a dim attribute is evaluable by this candidate
boolean	isExpressionEvaluable(org.apache.lens.cube.parse.ExpressionResolver.ExpressionContext expr) Checks whether an expression is evaluable by this candidate 1.
boolean	isExpressionEvaluable(String expr) Checks whether an expression is evaluable by this candidate 1.
boolean	isPhraseAnswerable(org.apache.lens.cube.parse.QueriedPhraseContext phrase) Checks whether the given queries phrase is evaluable by this candidate
boolean	isStorageTblsAtUpdatePeriodLevel() This will be true if this storage candidate has multiple storage tables (one per update period) https://issues.apache.org/jira/browse/LENS-1386
boolean	isTimeRangeCoverable(TimeRange timeRange) Is time range coverable based on valid update periods of this storage candidate
void	setFromString(String fromString)
void	setName(String name) Name of this storage candidate = storageName_factName
void	setResolvedName(String resolvedName) This is the storage table specific name.
void	setUpdatePeriodRejectionCause(Map<String,CandidateTablePruneCause.SkipUpdatePeriodCode> updatePeriodRejectionCause)
Collection<StorageCandidate>	splitAtUpdatePeriodLevelIfReq() Splits the Storage Candidates into multiple Storage Candidates if storage candidate has multiple storage tables (one per update period)
StorageCandidateHQLContext	toQueryWriterContext(Map<Dimension,CandidateDim> dimsToQuery, CubeQueryContext rootCubeQueryContext) Get query writer context from the candidate.
String	toString()

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.lens.cube.parse.Candidate

coveredPhrases, getChildrenCount, getConf, getCubeMetastoreClient, hasColumn, isColumnPresentAndValidForRange, isColumnValidForRange, isCompletelyValidForTimeRanges, isPartiallyValidForTimeRange, isPartiallyValidForTimeRanges, updateStorageCandidateQueriablePhraseIndices

Constructor Detail

StorageCandidate

public StorageCandidate(StorageCandidate sc)
                 throws LensException

Throws:

LensException

StorageCandidate

public StorageCandidate(CubeInterface cube,
                        FactTable fact,
                        String storageName,
                        CubeQueryContext cubeQueryContext)
                 throws LensException

Throws:

LensException

Method Detail

addAnswerableMeasurePhraseIndices

public void addAnswerableMeasurePhraseIndices(int index)

Description copied from interface: Candidate

Add `index` as answerable index in a pre-decided list of queried phrases.

Specified by:

addAnswerableMeasurePhraseIndices in interface Candidate

Parameters:

index - index to mark as answerable

explode

public Candidate explode()
                  throws LensException

Description copied from interface: Candidate

Explode this candidate into another candidate. Generally candidates can return `this` in this method Special case is storage candidate that returns UnionCandidate if there are multiple update periods covered and update periods have different tables.

Specified by:

explode in interface Candidate

Returns:

converted candidate

Throws:

LensException

getStorageString

public String getStorageString(String alias)

Description copied from interface: CandidateTable

Get storage string of the base table alias passed

Specified by:

getStorageString in interface CandidateTable

Returns:

storage string

getBaseTable

public AbstractCubeTable getBaseTable()

Description copied from interface: CandidateTable

Get base table of the candidate table

Specified by:

getBaseTable in interface CandidateTable

Returns:

Cube or DerivedCube or Dimesions

copy

public StorageCandidate copy()
                      throws LensException

Description copied from interface: Candidate

Clones this candidate

Specified by:

copy in interface Candidate

Returns:

the clone

Throws:

LensException - propagated exception

isPhraseAnswerable

public boolean isPhraseAnswerable(org.apache.lens.cube.parse.QueriedPhraseContext phrase)
                           throws LensException

Description copied from interface: Candidate

Checks whether the given queries phrase is evaluable by this candidate

Specified by:

isPhraseAnswerable in interface Candidate

Parameters:

phrase - Phrase to check

Returns:

whether the phrase is evaluable by this candidate

Throws:

LensException - propagated exception

getTable

public AbstractCubeTable getTable()

Description copied from interface: CandidateTable

Get candidate table

Specified by:

getTable in interface CandidateTable

Returns:

Candidate fact or dim table

getColumnStartTime

public Optional<Date> getColumnStartTime(String column)

Description copied from interface: Candidate

This method should give start time of a column, if there's any. Else, this should return Optional.absent

Specified by:

getColumnStartTime in interface Candidate

Parameters:

column - column name

Returns:

optional start time of this column

getColumnEndTime

public Optional<Date> getColumnEndTime(String column)

Description copied from interface: Candidate

This method should give end time of a column, if there's any. Else, this should return Optional.absent

Specified by:

getColumnEndTime in interface Candidate

Parameters:

column - column name

Returns:

optional end time of this column

getColumns

public Collection<String> getColumns()

Description copied from interface: Candidate

Returns all the fact columns

Specified by:

getColumns in interface Candidate

Specified by:

getColumns in interface CandidateTable

Returns:

collection of column names

getCost

public OptionalDouble getCost()

Specified by:

getCost in interface Candidate

Returns:

the cost of this candidate

contains

public boolean contains(Candidate candidate)

Description copied from interface: Candidate

Returns true if this candidate contains the given candidate

Specified by:

contains in interface Candidate

Parameters:

candidate - candidate to check

Returns:

whether this contains the candidate in question

getChildren

public Collection<Candidate> getChildren()

Description copied from interface: Candidate

Returns child candidates of this candidate if any. Note: StorageCandidate will return null

Specified by:

getChildren in interface Candidate

Returns:

child candidates if this is a complex candidate, else null

evaluateCompleteness

public boolean evaluateCompleteness(TimeRange timeRange,
                                    TimeRange queriedTimeRange,
                                    boolean failOnPartialData)
                             throws LensException

Description copied from interface: Candidate

Calculates if this candidate can answer the query for given time range based on actual data registered with the underlying candidate storages. This method will also update any internal candidate data structures that are required for writing the re-written query and to answer Candidate.getParticipatingPartitions().

Specified by:

evaluateCompleteness in interface Candidate

Parameters:

timeRange - : TimeRange to check completeness for. TimeRange consists of start time, end time and the partition column

queriedTimeRange - : User quried timerange

failOnPartialData - : fail fast if the candidate can answer the query only partially

Returns:

true if this Candidate can answer query for the given time range.

Throws:

LensException

getParticipatingPartitions

public Set<FactPartition> getParticipatingPartitions()

Description copied from interface: Candidate

Returns the set of fact partitions that will participate in this candidate. Note: This method can be called only after call to Candidate.evaluateCompleteness(TimeRange, TimeRange, boolean)

Specified by:

getParticipatingPartitions in interface Candidate

Specified by:

getParticipatingPartitions in interface CandidateTable

Returns:

a set of participating partitions

isExpressionEvaluable

public boolean isExpressionEvaluable(org.apache.lens.cube.parse.ExpressionResolver.ExpressionContext expr)

Description copied from interface: Candidate

Checks whether an expression is evaluable by this candidate 1. For a JoinCandidate, atleast one of the child candidates should be able to answer the expression 2. For a UnionCandidate, all child candidates should answer the expression

Specified by:

isExpressionEvaluable in interface Candidate

Parameters:

expr - Expression to be evaluated for Candidate

Returns:

Whether the given expression is evaluable or not

isExpressionEvaluable

public boolean isExpressionEvaluable(String expr)

Description copied from interface: Candidate

Checks whether an expression is evaluable by this candidate 1. For a JoinCandidate, atleast one of the child candidates should be able to answer the expression 2. For a UnionCandidate, all child candidates should answer the expression

Specified by:

isExpressionEvaluable in interface Candidate

Parameters:

expr - Expression to be evaluated for Candidate

Returns:

Whether the given expression is evaluable or not

isDimAttributeEvaluable

public boolean isDimAttributeEvaluable(String dim)
                                throws LensException

Description copied from interface: Candidate

Checks whether a dim attribute is evaluable by this candidate

Specified by:

isDimAttributeEvaluable in interface Candidate

Parameters:

dim - dim attribute

Returns:

whether the dim attribute is evaluable by this candidate

Throws:

LensException - propageted exception

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

Overrides:

toString in class Object

getAliasForTable

public String getAliasForTable(String alias)

isTimeRangeCoverable

public boolean isTimeRangeCoverable(TimeRange timeRange)
                             throws LensException

Is time range coverable based on valid update periods of this storage candidate

Specified by:

isTimeRangeCoverable in interface Candidate

Parameters:

timeRange -

Returns:

Throws:

LensException

getResolvedName

public String getResolvedName()

splitAtUpdatePeriodLevelIfReq

public Collection<StorageCandidate> splitAtUpdatePeriodLevelIfReq()
                                                           throws LensException

Splits the Storage Candidates into multiple Storage Candidates if storage candidate has multiple storage tables (one per update period)

Returns:

Throws:

LensException

toQueryWriterContext

public StorageCandidateHQLContext toQueryWriterContext(Map<Dimension,CandidateDim> dimsToQuery,
                                                       CubeQueryContext rootCubeQueryContext)
                                                throws LensException

Description copied from interface: Candidate

Get query writer context from the candidate. Default implementation is for Union, Join and Segmentation candidates. In the default implementation, a MultiCandidateQueryWriterContext is returned, whose children are obtained by getting the query writer contexts from the children of this candidate.

Specified by:

toQueryWriterContext in interface Candidate

Parameters:

dimsToQuery - Dimensions and corresponding picked CandidateDim for query

rootCubeQueryContext - Root query context.

Returns:

A Query Writer Context

Throws:

LensException - exception to be propagated

decideMeasurePhrasesToAnswer

public Set<Integer> decideMeasurePhrasesToAnswer(Set<Integer> measureIndices)

Specified by:

decideMeasurePhrasesToAnswer in interface Candidate

getCubeQueryContext

@Generated(value="lombok")
public CubeQueryContext getCubeQueryContext()

Description copied from interface: Candidate

A candidate always works along with its cube query context. So a top level method to retrieve that.

Specified by:

getCubeQueryContext in interface Candidate

Returns:

cube query context for this candidate.

getName

@Generated(value="lombok")
public String getName()

Name of this storage candidate = storageName_factName

Specified by:

getName in interface Named

setName

@Generated(value="lombok")
public void setName(String name)

Name of this storage candidate = storageName_factName

setResolvedName

@Generated(value="lombok")
public void setResolvedName(String resolvedName)

This is the storage table specific name. It is used while generating query from this candidate

getValidUpdatePeriods

@Generated(value="lombok")
public TreeSet<UpdatePeriod> getValidUpdatePeriods()

Valid update periods populated by Phase 1.

getParticipatingUpdatePeriods

@Generated(value="lombok")
public TreeSet<UpdatePeriod> getParticipatingUpdatePeriods()

These are the update periods that finally participate in partitions.

See Also:

getParticipatingPartitions()

getUpdatePeriodRejectionCause

@Generated(value="lombok")
public Map<String,CandidateTablePruneCause.SkipUpdatePeriodCode> getUpdatePeriodRejectionCause()

setUpdatePeriodRejectionCause

@Generated(value="lombok")
public void setUpdatePeriodRejectionCause(Map<String,CandidateTablePruneCause.SkipUpdatePeriodCode> updatePeriodRejectionCause)

getQueriedDims

@Generated(value="lombok")
public Set<Dimension> getQueriedDims()

getDataCompletenessMap

@Generated(value="lombok")
public Map<String,Map<String,Float>> getDataCompletenessMap()

This map holds Tags (A tag refers to one or more measures) that have incomplete (below configured threshold) data. Value is a map of date string and %completeness.

getFact

@Generated(value="lombok")
public FactTable getFact()

Participating fact, storage and dimensions for this StorageCandidate

getStorageName

@Generated(value="lombok")
public String getStorageName()

getStorageTable

@Generated(value="lombok")
public String getStorageTable()

Description copied from interface: CandidateTable

Get storage table corresponding to this candidate

Specified by:

getStorageTable in interface CandidateTable

Returns:

getRangeToPartitions

@Generated(value="lombok")
public Map<TimeRange,Set<FactPartition>> getRangeToPartitions()

getRangeToExtraWhereFallBack

@Generated(value="lombok")
public Map<TimeRange,String> getRangeToExtraWhereFallBack()

getAnswerableMeasurePhraseIndices

@Generated(value="lombok")
public Set<Integer> getAnswerableMeasurePhraseIndices()

Description copied from interface: Candidate

Gets the index positions of answerable measure phrases in CubeQueryContext#selectPhrases

Specified by:

getAnswerableMeasurePhraseIndices in interface Candidate

Returns:

set of indices of answerable phrases

getFromString

@Generated(value="lombok")
public String getFromString()

setFromString

@Generated(value="lombok")
public void setFromString(String fromString)

getCube

@Generated(value="lombok")
public CubeInterface getCube()

Description copied from interface: Candidate

Utility method to return cube of its cube query context

Specified by:

getCube in interface Candidate

Returns:

getCubeQueryContext().getCube()

getStartTime

@Generated(value="lombok")
public Date getStartTime()

Description copied from interface: Candidate

Start Time for this candidate (calculated based on schema)

Specified by:

getStartTime in interface Candidate

Returns:

start time of this candidate

getEndTime

@Generated(value="lombok")
public Date getEndTime()

Description copied from interface: Candidate

End Time for this candidate (calculated based on schema)

Specified by:

getEndTime in interface Candidate

Returns:

end time of this candidate

getNonExistingPartitions

@Generated(value="lombok")
public Set<String> getNonExistingPartitions()

Non existing partitions

isStorageTblsAtUpdatePeriodLevel

@Generated(value="lombok")
public boolean isStorageTblsAtUpdatePeriodLevel()

This will be true if this storage candidate has multiple storage tables (one per update period) https://issues.apache.org/jira/browse/LENS-1386

getNumQueriedParts

@Generated(value="lombok")
public int getNumQueriedParts()