Extensions v1.10.0

In this release

• Updates to the input specification for createVizImageAsync. This release includes support for combination charts, charts with multiple mark types in the same visualization (requires Tableau 2022.4+).
• Adds support for a DataTableReader to support pagination (requires Tableau 2022.4+).
• Deprecated Worksheet.getSummaryDataAsync. Use Worksheet.getSummaryDataReaderAsync.
• UI.displayDialogAsync now supports different dialog styles (window, modal or modeless dialog boxes).
• Adds support for annotating marks with Worksheet.annotateMarkAsync, Worksheet.getAnnotationsAsync, and Worksheet.removeAnnotationAsync.
• Map file is now included for better debugging experience with minified library.
• See other details in https://tableau.github.io/extensions-api/docs/trex_release-notes.html.

DataTableReader Introduction

There has always been a 10k row limit on getUnderlyingTableDataAsync and on
getLogicalTableDataAsync, and for large worksheets, getSummaryDataAsync can prove to be
unreliable.

Introducting DataTableReader! Starting with Tableau 2022.4 and Extensions v1.10.0,
DataTableReader provides an API to request data a page at a time.

Fetching a DataTableReader

To get a DataTableReader use one of the new functions: getSummaryDataReaderAsync,
getUnderlyingTableDataReaderAsync, or getLogicalTableDataReaderAsync. The parameters to these
functions include the GetSummaryDataOptions or GetUnderlyingDataOptions, but also include a page
row count. This parameter sets the size of pages that will be returned. The default, and maximum,
page size is 10,000 rows.

Using a DataTableReader

Converting your code to use a DataTableReader is straightforward.

The following:

const dataTable = await this.worksheet.getSummaryDataAsync();
// ... use dataTable ...

becomes:

const dataTableReader = await this.worksheet.getSummaryDataReaderAsync();
const dataTable = await dataTableReader.getAllPagesAsync();
await dataTableReader.releaseAsync();
// ... use dataTable ...

Or alternatively:

const dataTableReader = await this.worksheet.getSummaryDataReaderAsync();
for (let currentPage = 0; currentPage < dataTableReader.pageCount; currentPage++) {
    const currentPageDataTable = await dataTableReader.getPageAsync(currentPage);
    // ... process currentPageDataTable ...
}
await dataTableReader.releaseAsync();

Limits on a DataTableReader

Unfortunately, we still live a a world with limited computing resources. A DataTableReader consumes
server resources. Therefore, there are still limits on the number of rows supported for underlying
and logical data table readers. The default limit is approximately 1 million rows of data for
getUnderlyingTableDataReaderAsync, and approximately 32 million cells (rows * columns) for
getLogicalTableDataReaderAsync. Server administrators (starting in 2023.1) may change these limits to better match
computing resources with the Tableau Server (Cloud) or Tableau Desktop options:

• ExtensionsAndEmbeddingReaderRowLimit for getUnderlyingTableDataReaderAsync or
• ExtensionsAndEmbeddingReaderCellLimit for getLogicalTableDataReaderAsync.

Hints on using a DataTableReader

• If you are dealing with large amounts of data, set the columns to include, or the
  IncludeDataValuesOption to what you need. Fetching all columns, or requesting formatted data
  when you don't need various column or formatted data take significantly more time and resources.
  The option IncludeDataValuesOption.OnlyNativeValues is your friend for very large underlying or logical
  table data.
• Only one DataTableReader per logical table id is supported.
• Call DataTableReader.releaseAsync() when you are done processing the data. You can always
  request another one if you need to do more processing after some period of inactivity or user
  action.