ComponentOne ASP.NET MVC Controls
PivotEngine Class
File
wijmo.olap.js
Module
wijmo.olap

Provides a user interface for interactively transforming regular data tables into Olap pivot tables.

Tabulates data in the itemsSource collection according to lists of fields and creates the pivotView collection containing the aggregated data.

Pivot tables group data into one or more dimensions. The dimensions are represented by rows and columns on a grid, and the data is stored in the grid cells.

Constructor

Properties

Methods

Events

Constructor

constructor

constructor(options?: any): PivotEngine

Initializes a new instance of the PivotEngine class.

Parameters
Optional

JavaScript object containing initialization data for the field.

Returns
PivotEngine

Properties

allowFieldEditing

Gets or sets a value that determines whether users should be allowed to edit the properties of the PivotField objects owned by this PivotEngine.

If you set this property to false, the context menus shown by controls such as the PivotGrid and PivotPanel will not include an option for changing the field settings.

The default value for this property is true.

Type
boolean

async

Gets or sets a value that determines whether view updates should be generated asynchronously.

This property is set to true by default, so summaries over large data sets are performed asynchronously to prevent stopping the UI thread.

The default value for this property is true.

Type
boolean

autoGenerateFields

Gets or sets a value that determines whether the engine should generate fields automatically based on the itemsSource.

If you set this property to true, the engine will generate fields for each property of the items in the itemsSource. The binding property of the auto-generated fields is set to the property name, and their header property is set to a string obtained by capitalizing the first letter of the binding and adding spaces before each capital letter.

For example, a 'customerName' property will cause the engine create a field with binding set to 'customerName' and header set to 'Customer Name'.

When adding fields to one of the view lists using strings, you must specify the header, not the binding (unlike bindings, field headers must be unique).

The default value for this property is true.

Type
boolean

collectionView

Gets the ICollectionView that contains the raw data.

Type
ICollectionView

columnFields

Gets the list of PivotField objects that define the fields shown as columns in the output table.

Type
PivotFieldCollection

defaultFilterType

Gets or sets the default filter type (by value or by condition).

The default value for this property is null, which causes the engine to use FilterType.Both on the client or FilterType.Condition on the server.

Type
FilterType

exclusiveValueSearch

Gets or sets a value that determines whether the filter should include only values selected by the filterText property.

This property is set to true by default, which matches Excel's behavior.

Set it to false to disable this behavior, so searching only affects which items are displayed on the list and not which items are included in the filter.

Type
boolean

fields

Gets the list of PivotField objects exposed by the data source.

This list is created automatically whenever the itemsSource property is set.

Pivot views are defined by copying fields from this list to the lists that define the view: valueFields, rowFields, columnFields, and filterFields.

For example, the code below assigns a data source to the PivotEngine and then defines a view by adding fields to the rowFields, columnFields, and valueFields lists.

// create pivot engine
var pe = new wijmo.olap.PivotEngine();

// set data source (populates fields list)
pe.itemsSource = this.getRawData();

// prevent updates while building Olap view
pe.beginUpdate();

// show countries in rows
pe.rowFields.push('Country');

// show categories and products in columns
pe.columnFields.push('Category');
pe.columnFields.push('Product');

// show total sales in cells
pe.valueFields.push('Sales');

// done defining the view
pe.endUpdate();
Type
PivotFieldCollection

filterFields

Gets the list of PivotField objects that define the fields used as filters.

Fields on this list do not appear in the output table, but are still used for filtering the input data.

Type
PivotFieldCollection

isServer

Gets a value that determines whether the engine is bound to a server itemsSource or is using local data.

Type
boolean

isUpdating

Gets a value that indicates whether the engine is currently being updated.

Type
boolean

isViewDefined

Gets a value that determines whether a pivot view is currently defined.

A pivot view is defined if any of the valueFields, rowFields, or columnFields lists are not empty.

Type
boolean

itemsSource

Gets or sets the array or ICollectionView that contains the raw data to be analyzed, an object describing an SSAS cube service, or a string containing the URL for a ComponentOne DataEngine service.

The first option (using an array or ICollectionView) is the simplest, but it limits the amount of raw data you can handle. Loading the raw data into an array can take a long time if the data set contains more than about 50,000 items or so.

To use this option, simply set the itemsSource property to any JavaScript array containing the raw data to be analyzed. For example:

var ng = new wijmo.olap.PivotEngine({
    itemsSource = getDataArray(1000);
});

The second option (direct connection to OLAP SSAS cubes) allows the PivotEngine to connect directly to OLAP cubes provided by SSAS servers. This option removes the size limitations mentioned above and allows you to analyze data sets with millions or billions of records.

To use this option, set the itemsSource property to an object with two members, url and cube, that specify how the component should access the service. For example:

var ng = new wijmo.olap.PivotEngine({
    itemsSource: {
        url: 'http://ssrs.componentone.com/OLAP/msmdpump.dll',
        cube: 'Adventure Works'
    }
});

When connecting directly to OLAP SSAS cubes, users will not be able to filter fields by value. They will still be able to filter by condition.

The third option, ComponentOne data engine services, allows you to analyze large datasets on a server without downloading the raw data to the client. You can use our high-performance FlexPivot services or interface with Microsoft's SQL Server Analysis Services OLAP Cubes.

To use ComponentOne data engine services, set the itemsSource property to a string containing the URL of the data service. For example:

var ng = new wijmo.olap.PivotEngine({
    itemsSource: 'http://demos.componentone.com/ASPNET/c1webapi/4.0.20173.114/api/dataengine/cube'
});

The PivotEngine sends view definitions to the server, where summaries are calculated and returned to the client.

When connecting ComponentOne DataEngine data sources, users will not be able to filter fields by value. They will still be able to filter by condition.

For more information about the ComponentOne DataEngine services please refer to the online documentation.

Our OlapServerIntro sample shows all options working with a single PivotEngine.

Type
any

pivotView

Gets the ICollectionView containing the output pivot view.

Type
ICollectionView

rowFields

Gets the list of PivotField objects that define the fields shown as rows in the output table.

Type
PivotFieldCollection

serverMaxDetail

Gets or sets the maximum number of records the getDetail method should retrieve from the server.

The default value for this property is 1,000, which is a reasonable amount of detail in many scenarios. If you want to allow more detail records to be retrieved, increase the value of this property.

Type
number

serverPollInterval

Gets or sets the amount of time, in milliseconds, that the engine should wait before polling the server for progress status while retrieving results.

The default value for this property is 500 milliseconds, which causes the engine to poll the server for a status update every half second.

Type
number

serverTimeout

Gets or sets the maximum amount of time, in milliseconds, that the engine should wait for the results to come back from the server.

The default value for this property is 60,000 milliseconds, or one minute. If you expect server operations to take longer than that, set the property to a higher value.

Type
number

showColumnTotals

Gets or sets a value that determines whether the output pivotView should include columns containing subtotals or grand totals.

The default value for this property is ShowTotals.GrandTotals.

Type
ShowTotals

showRowTotals

Gets or sets a value that determines whether the output pivotView should include rows containing subtotals or grand totals.

The default value for this property is ShowTotals.GrandTotals.

Type
ShowTotals

showZeros

Gets or sets a value that determines whether the Olap output table should use zeros to indicate the missing values.

The default value for this property is false.

Type
boolean

sortableGroups

Gets or sets a value that determines whether the engine should sort groups when sorting the value fields (measures) or whether it should keep the group order and the data only within each group.

The default value for this property is true.

Type
boolean

sortOnServer

Gets or sets a value that indicates whether the summary data received from the server is already sorted.

If this property is set to true, the PivotEngine will not sort the data it receives from the server.

This property should be used only in conjunction with custom servers that return the aggregated data properly sorted, typically using custom logic not available in the standard PivotEngine.

The default value for this property is false.

Type
boolean

totalsBeforeData

Gets or sets a value that determines whether row and column totals should be displayed before or after regular data rows and columns.

If this value is set to true, total rows appear above data rows and total columns appear on the left of regular data columns.

The default value for this property is false.

Type
boolean

valueFields

Gets the list of PivotField objects that define the fields summarized in the output table.

Type
PivotFieldCollection

viewDefinition

Gets or sets the current pivot view definition as a JSON string.

This property is typically used to persist the current view as an application setting.

For example, the code below implements two functions that save and load view definitions using local storage:

// save/load views
function saveView() {
  localStorage.viewDefinition = pivotEngine.viewDefinition;
}
function loadView() {
  pivotEngine.viewDefinition = localStorage.viewDefinition;
}
Type
string

Methods

beginUpdate

beginUpdate(): void

Suspends the refresh processes until next call to the endUpdate.

Returns
void

cancelPendingUpdates

cancelPendingUpdates(): void

Cancels any pending asynchronous view updates.

Returns
void

deferUpdate

deferUpdate(fn: Function): void

Executes a function within a beginUpdate/endUpdate block.

The control will not be updated until the function has been executed. This method ensures endUpdate is called even if the function throws an exception.

Parameters
Returns
void

editField

editField(field: PivotField): void

Shows a settings dialog where users can edit a field's settings.

Parameters
Returns
void

endUpdate

endUpdate(): void

Resumes refresh processes suspended by calls to beginUpdate.

Returns
void

getDetail

getDetail(item: any, binding: string): any[]

Gets an array containing the records summarized by a property in the pivotView list.

If the engine is connected to a PivotEngine server, the value returned is an ObservableArray that is populated asynchronously.

Parameters
  • item: any

    Data item in the pivotView list.

  • binding: string

    Name of the property being summarized.

Returns
any[]

getDetailView

getDetailView(item: any, binding: string): ICollectionView

Gets an ICollectionView containing the records summarized by a property in the pivotView list.

Parameters
  • item: any

    Data item in the pivotView list.

  • binding: string

    Name of the property being summarized.

Returns
ICollectionView

getKeys

getKeys(item: any, binding: string): any

Gets an object with information about a property in the pivotView list.

The object returned has two properties, 'rowKey' and 'colKey'. Each of these contains two arrays, 'fields' and 'values'. Together, this information uniquely identifies a value summarized by the PivotEngine.

For example, calling getKeys against a pivot view with two row fields 'Product' and 'Country', and a single column field 'Active' would return an object such as this one:

{
    rowKey: {
        fields: [ 'Product', 'Country'],
        values: [ 'Aoba', 'Japan' ]
    },
    colKey: {
        fields: [ 'Active' ],
        values: [ true ]
    }
}

The object identifies the subset of data used to obtain one summary value. In this case, this value represents all data items for product 'Aoba' sold in Japan with Active state set to true.

Parameters
  • item: any

    Data item in the pivotView list.

  • binding: string

    Name of the property being summarized.

Returns
any

invalidate

invalidate(): void

Invalidates the view causing an asynchronous refresh.

Returns
void

onError

onError(e: RequestErrorEventArgs): boolean

Raises the error event.

Parameters
Returns
boolean

onItemsSourceChanged

onItemsSourceChanged(e?: EventArgs): void

Raises the itemsSourceChanged event.

Parameters
Optional
Returns
void

onUpdatedView

onUpdatedView(e?: EventArgs): void

Raises the updatedView event.

Parameters
Optional
Returns
void

onUpdatingView

onUpdatingView(e: ProgressEventArgs): void

Raises the updatingView event.

Parameters
Returns
void

onViewDefinitionChanged

onViewDefinitionChanged(e?: EventArgs): void

Raises the viewDefinitionChanged event.

Parameters
Returns
void

refresh

refresh(force?: boolean): void

Summarizes the data and updates the output pivotView.

Parameters
Returns
void

removeField

removeField(field: PivotField): void

Removes a field from the current view.

Parameters
Returns
void

Events

error

Occurs when there is an error getting data from the server.

Arguments
RequestErrorEventArgs

itemsSourceChanged

Occurs after the value of the itemsSource property changes.

Arguments
EventArgs

updatedView

Occurs after the engine has finished updating the pivotView list.

Arguments
EventArgs

updatingView

Occurs when the engine starts updating the pivotView list.

Arguments
ProgressEventArgs

viewDefinitionChanged

Occurs after the view definition changes.

Arguments
EventArgs