Package org.apache.drill.exec.udfs

Class DateFunctions.NearestDateFunction

java.lang.Object

org.apache.drill.exec.udfs.DateFunctions.NearestDateFunction

All Implemented Interfaces:

DrillFunc, DrillSimpleFunc

Enclosing class:

DateFunctions

public static class DateFunctions.NearestDateFunction
extends Object
implements DrillSimpleFunc

This function takes two arguments, an input date object, and an interval and returns the previous date that is the first date in that period. This function is intended to be used in time series analysis to aggregate by various units of time. Usage is:

SELECT , COUNT(*) AS event_count FROM ... GROUP BY nearestDate(`date_field`, 'QUARTER')

Currently supports the following time units:

YEAR QUARTER MONTH WEEK_SUNDAY WEEK_MONDAY DAY HOUR HALF_HOUR QUARTER_HOUR MINUTE 30SECOND 15SECOND SECOND

Constructor Summary

Constructors

Constructor	Description
NearestDateFunction()

Method Summary

Modifier and Type	Method	Description
void	eval()
void	setup()

Methods inherited from class java.lang.Object

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

Constructor Details

NearestDateFunction

public NearestDateFunction()

Method Details

setup

public void setup()

Specified by:

setup in interface DrillSimpleFunc

eval

public void eval()

Specified by:

eval in interface DrillSimpleFunc