Package org.apache.drill.exec.udfs

Class DateFunctions.NearestDateFunctionWithString

java.lang.Object

org.apache.drill.exec.udfs.DateFunctions.NearestDateFunctionWithString

All Implemented Interfaces:

DrillFunc, DrillSimpleFunc

Enclosing class:

DateFunctions

public static class DateFunctions.NearestDateFunctionWithString
extends Object
implements DrillSimpleFunc

This function takes three arguments, an input date string, an input date format string, 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`, 'yyyy-mm-dd', '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
NearestDateFunctionWithString()

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

NearestDateFunctionWithString

public NearestDateFunctionWithString()

Method Details

setup

public void setup()

Specified by:

setup in interface DrillSimpleFunc

eval

public void eval()

Specified by:

eval in interface DrillSimpleFunc