DataSources and DataSets references in a paginated report (Report Builder)
Applies to: 
Microsoft Report Builder (SSRS)
Power BI Report Builder
Report Designer in SQL Server Data Tools
The DataSources collection represents all the data sources used in a paginated report. Similarly, the DataSets collection represents all the datasets for all the data sources in a report. Use the Report Data pane for a hierarchical view of report datasets organized under the data source they reference. If you include references to these collections, you see values when previewing your report. These collections are only available after the report is published to a report server.
Note
You can create and modify paginated report definition (.rdl) files in Microsoft Report Builder, Power BI Report Builder, and in Report Designer in SQL Server Data Tools.
DataSources
The DataSources collection represents the data sources referenced in a published report definition. You might choose to include this information in your report to document the source of the report data. This collection isn't available in Preview mode. The following table describes the variables within the DataSources collection.
| Variable | Type | Description |
|---|---|---|
| DataSourceReference | String | The full path of the data source definition on the report server. For example, you might include a list of all the data sources a report used as part of a report history. The following example shows the full path for the data source named AdventureWorks2022:/DataSources/AdventureWorks2022. |
| Type | String | The type of data provider for the data source. For example, SQL. |
DataSets
The DataSets collection represents the datasets referenced in a report definition. You might choose to include the query in the report in a text box, so a user interested in exactly which data is in the report can see the original command text. This collection isn't available in Preview mode. The following table describes the members of the DataSets collection.
| Member | Type | Description |
|---|---|---|
| CommandText | String | For database data sources, this query is the query used to retrieve data from the data source. If the query is an expression, this expression is the evaluated expression. |
| RewrittenCommandText | String | The data provider's expanded CommandText value. This value is typically used for reports with query parameters that are mapped to report parameters. The data provider sets this property when expanding the command text parameter references into the constant values selected for the mapped report parameters. |
Use Query Expressions
You can use expressions to define the query that is contained in a dataset. You can use this feature to design reports in which the query changes based on input from the user, data in other datasets, or other variables. For more information about queries, see Report embedded datasets and shared datasets (Report Builder).