Package com.inductiveautomation.historian.gateway.query.aggregates

Class MinMaxAggregate

java.lang.Object

com.inductiveautomation.historian.gateway.query.aggregates.MinMaxAggregate

All Implemented Interfaces:

AggregationFunction

public class MinMaxAggregate
extends Object
implements AggregationFunction

Created by colby.clegg on 8/10/2015.

Constructor Summary

Constructors

Constructor	Description
MinMaxAggregate(AggregationMode mode)	Mode should be Minimum, Maximum, MinMax, or Range

Method Summary

Modifier and Type	Method	Description
protected boolean	isMax(QualifiedValue val, QualifiedValue max)
protected boolean	isMin(QualifiedValue val, QualifiedValue min)
QualifiedValue[]	process(QualifiedValue pv, boolean interpolatedValue, boolean blockFinished, BlockContext blockContext, QueryContext queryContext)	This function will be called for each value that should be processed, for the entire range of the query.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.inductiveautomation.ignition.gateway.sqltags.history.query.processing.AggregationFunction

getDataType, supportsDataType

Constructor Details

MinMaxAggregate

public MinMaxAggregate(AggregationMode mode)

Mode should be Minimum, Maximum, MinMax, or Range

Method Details

process

public QualifiedValue[] process(@Nullable
 QualifiedValue pv,
 boolean interpolatedValue,
 boolean blockFinished,
 BlockContext blockContext,
 QueryContext queryContext)

Description copied from interface: AggregationFunction

This function will be called for each value that should be processed, for the entire range of the query. It works in the following way:

1. For each window, a new BlockContext is created. This object provides some information, but can also be used as a scratch pad for data in the aggregation window.
2. The function will be called for each value that is actually read from the data source. In this case, interpolatedValue will be false
3. The function will be called with values at the start of the window and at the end of the window. In these cases, the interpolatedValue boolean will be true (unless raw values just happen to correspond exactly).
4. The BlockContext contains the previous raw and computed values prior to this block, which can be used for running sums, ongoing calculations, etc.
5. The return value is only used when blockFinished is true. At the end of the window, the function will be called with an interpolated value for the end time, and blockFinished=true. The function should finalize calculations and return results. (* The function may reuse the return array, and mutate it after returning values)

Specified by:

process in interface AggregationFunction

isMin

protected boolean isMin(QualifiedValue val,
 QualifiedValue min)

isMax

protected boolean isMax(QualifiedValue val,
 QualifiedValue max)