Time-over-Time Comparison
Time-over-time comparison allows you to add a measure representing data from the past and compare it to another measure in a visualization. The visualization must contain at least one measure that the measure with the data from the past can reference.
The measure with the data from the past is called derived measure. The referenced measure is called master measure.
You can compare data to:
- The same period previous year
- The previous period
We do not recommend that you create a derived measure from an arithmetic measure that refers to another derived measure. The resulting derived measure may be hard to interpret.
Comparing to the same period (SP) previous year
Time shift: -1 year
Period: 1 year
To add a SP derived measure to a visualization, use the following newPopMeasure
factory function:
newPopMeasure(masterMeasureOrLocalId, overPeriodAttributeId, modifications)
where:
masterMeasureOrLocalId
is the measure with data to compare; specify either the measure’slocalIdentifier
or the measure itself.overPeriodAttributeId
is the identifier of the date dimension year attribute to use for the shift.modifications
is a function that receives an object with functions to customizeformat()
andalias()
.
Example
import { PivotTable } from "@gooddata/sdk-ui-pivot";
import { newMeasure, newPopMeasure } from "@gooddata/sdk-model";
const masterMeasure = newMeasure("measureIdentifier", m => m.alias("Master Measure"));
const popMeasure = newPopMeasure(masterMeasure, "attributeYearIdentifier", m => m.alias("Same Period Previous Year"));
const measures = [
masterMeasure,
popMeasure
];
<PivotTable
measures={measures}
/>
Comparing to the previous period (PP)
Time shift: a specified number of periods
Period: defined by global date filters referenced by the date dataset URI or identifier in the derived measure definition
- For an absolute date filter, the period is N days.
- For a relative date filter, the period can be N days, weeks, months, quarters, or years depending on the selected granularity.
If no global date filter is defined, the derived measure returns the same data as the master measure.
To add a PP derived measure to a visualization, use the following newPreviousPeriodMeasure
factory function:
newPreviousPeriodMeasure(masterMeasureOrLocalId, dateDataSetsShift, modifications);
where:
masterMeasureOrLocalId
is the measure with data to compare; specify either the measure’slocalIdentifier
or the measure itself.dateDataSetsShift
is the definition of the period shift to apply; it is an object with thedataSet
prop for the date dataset identifier and theperiodsAgo
prop to specify the period shift.modifications
is a fucntion that receives an object with functions to customizeformat()
andalias()
.
Example
import { newMeasure, newPreviousPeriodMeasure, newRelativeDateFilter } from "@gooddata/sdk-model";
import { PivotTable } from "@gooddata/sdk-ui-pivot";
const filters = [
newRelativeDateFilter("dateDatasetIdentifier", "GDC.time.date", -7, -1)
];
// master - last 7 days measure
const masterMeasure = newMeasure("measureIdentifier", m => m.alias("Master Measure"));
// derived - previous 7 days measure
const previousPeriod = newPreviousPeriodMeasure(
masterMeasure,
{ dataSet: "dateDatasetIdentifier", periodsAgo: 1},
m => m.alias("Previous Period Measure")
);
const measures = [
masterMeasure,
previousPeriod
];
<PivotTable
measures={measures}
filters={filters}
/>
Comparison to the PP and absolute date filters
Be careful when combining comparison to the PP with an absolute date filter. For example, when filtering from March 1 to March 31, the previous period is the previous 31 days and not the previous month. For comparing over a period other than a day, use a relative date filter with the required granularity (month, quarter).
Time over time comparison and week date filters
If you use date filters by weeks and compare the data to the previous period or the same period of the last year in those filters, you have to enable the GoodData platform to properly process such week filters. To do so, complete the following steps:
Switch the version of the Extensible Analytics Engine to 3.
To do so, set the
xae_version
platform setting to 3 (see Configure Various Features via Platform Settings).Migrate the Date datasets in your workspace to the
urn:custom_v2:date
date dimension.To do so, see “Migrate from a Legacy Date Dimension to urn:custom_v2:date” in Manage Custom Date Dimensions.
More examples
See the live examples.