程序包 org.apache.iotdb.db.query.aggregation.impl

类 FirstValueDescAggrResult

java.lang.Object

org.apache.iotdb.db.query.aggregation.AggregateResult

org.apache.iotdb.db.query.aggregation.impl.FirstValueAggrResult

org.apache.iotdb.db.query.aggregation.impl.FirstValueDescAggrResult

所有已实现的接口:

java.lang.Cloneable

public class FirstValueDescAggrResult
extends FirstValueAggrResult

字段概要

从类继承的字段 org.apache.iotdb.db.query.aggregation.AggregateResult

hasCandidateResult, resultDataType, TIME_LENGTH_FOR_FIRST_VALUE, timestamp

构造器概要

构造器

构造器	说明
FirstValueDescAggrResult(org.apache.iotdb.tsfile.file.metadata.enums.TSDataType dataType)

方法概要

修饰符和类型	方法	说明
boolean	hasFinalResult()	Judge if aggregation results have been calculated.
boolean	isAscending()	Whether the AggregationResult accepts data in time ascending order, if it returns false, the data should be passed in time descending order.
void	updateResultFromPageData(org.apache.iotdb.tsfile.read.common.IBatchDataIterator batchIterator, long minBound, long maxBound)	Aggregate results cannot be calculated using Statistics directly, using the data in each page.
void	updateResultFromStatistics(org.apache.iotdb.tsfile.file.metadata.statistics.Statistics statistics)	Calculate the aggregation using Statistics
void	updateResultUsingTimestamps(long[] timestamps, int length, IReaderByTimestamp dataReader)	This method calculates the aggregation using common timestamps of the cross series filter.
void	updateResultUsingValues(long[] timestamps, int length, ValueIterator valueIterator)	This method calculates the aggregation using values that have been calculated

从类继承的方法 org.apache.iotdb.db.query.aggregation.impl.FirstValueAggrResult

deserializeSpecificFields, getResult, merge, reset, serializeSpecificFields, updateResultFromPageData

从类继承的方法 org.apache.iotdb.db.query.aggregation.AggregateResult

clone, deserializeFrom, getAggregationType, getBinaryValue, getBooleanValue, getDoubleAbsValue, getDoubleValue, getFloatAbsValue, getFloatValue, getIntAbsValue, getIntValue, getLongAbsValue, getLongValue, getResultDataType, getTime, getValue, hasCandidateResult, serialize, serializeTo, setBinaryValue, setBooleanValue, setDoubleValue, setFloatValue, setIntValue, setLongValue, setTime, setValue, toString

从类继承的方法 java.lang.Object

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

构造器详细资料

FirstValueDescAggrResult

public FirstValueDescAggrResult(org.apache.iotdb.tsfile.file.metadata.enums.TSDataType dataType)

方法详细资料

updateResultFromStatistics

public void updateResultFromStatistics(org.apache.iotdb.tsfile.file.metadata.statistics.Statistics statistics)

从类复制的说明: AggregateResult

Calculate the aggregation using Statistics

覆盖:

updateResultFromStatistics 在类中 FirstValueAggrResult

参数:

statistics - chunkStatistics or pageStatistics

updateResultFromPageData

public void updateResultFromPageData(org.apache.iotdb.tsfile.read.common.IBatchDataIterator batchIterator,
                                     long minBound,
                                     long maxBound)

从类复制的说明: AggregateResult

Aggregate results cannot be calculated using Statistics directly, using the data in each page. This method is used in GROUP BY aggregation query.

覆盖:

updateResultFromPageData 在类中 FirstValueAggrResult

参数:

batchIterator - the data in Page

minBound - calculate points whose time >= bound

maxBound - calculate points whose time < bound

updateResultUsingTimestamps

public void updateResultUsingTimestamps(long[] timestamps,
                                        int length,
                                        IReaderByTimestamp dataReader)
                                 throws java.io.IOException

从类复制的说明: AggregateResult

This method calculates the aggregation using common timestamps of the cross series filter.

覆盖:

updateResultUsingTimestamps 在类中 FirstValueAggrResult

抛出:

java.io.IOException - TsFile data read error

updateResultUsingValues

public void updateResultUsingValues(long[] timestamps,
                                    int length,
                                    ValueIterator valueIterator)

从类复制的说明: AggregateResult

This method calculates the aggregation using values that have been calculated

覆盖:

updateResultUsingValues 在类中 FirstValueAggrResult

isAscending

public boolean isAscending()

从类复制的说明: AggregateResult

Whether the AggregationResult accepts data in time ascending order, if it returns false, the data should be passed in time descending order.

覆盖:

isAscending 在类中 AggregateResult

hasFinalResult

public boolean hasFinalResult()

从类复制的说明: AggregateResult

Judge if aggregation results have been calculated. In other words, if the aggregated result does not need to compute the remaining data, it returns true.

覆盖:

hasFinalResult 在类中 FirstValueAggrResult

返回:

If the aggregation result has been calculated return true, else return false.