Issue

User cannot sort or filter columns whose values are populated or modified by a Response Data Transform when the table is sourced from a queryable Data Page that uses a Report Definition.  When users attempt to sort or filter columns whose values are populated or modified by the Response Data Transform, the operation fails or returns empty filter values.

Symptoms and Impact

This issue occurs in the following scenario: 

1. The Data Page is configured as a List, Read-only, scoped to Thread or Requestor, and sourced from a Report Definition. 
2. "Allow querying any column (Pega connection only)" is enabled on the Data Page. 
3. Response Data Transform or post-load Activity modifies or populates new column based on the values returned by the Report Definition. 
4. Filter / Sorting is done on the new populated column/modified value 

Steps to reproduce

1. Create a Report Definition that returns a date field (Field A). 
2. Create a Data Page using the Report Definition as the data source. 
3. Enable Allow querying any column on the Data Page. 
4. Create a Response Data Transform and map .FieldB = pxPages(X).FieldA. 
5. Configure a table/grid and use Field B as the date column. 
6. Enable Optimize Code on the grid layout. 
7. Run the application and open the table. 
8. Attempt to sort or filter using the date column (Field B). Result: The date values are displayed correctly in the table, but sorting and filtering do not work as expected. Expected Result: Sorting and filtering should work correctly on the displayed date values. 

Root Cause

This is the documented product limitation for queryable Data Pages backed by a Report Definition. When a Response Data Transform modifies or populates values after the query executes, the queryable Data Page cannot pass those transformed values back as filter/sort criteria to the database — because the transformation happens in-memory on the clipboard, after the query has already run. Filtering and sorting on a queryable Data Page is a database-side operation; it cannot act on values that only exist after post-processing.  

When "Allow querying any column" is enabled on a Data Page, the platform delegates sorting, filtering, and export operations directly to the Report Definition at database query time. This happens before the Clipboard is populated, and before any Response Data Transform or post-load activity has the opportunity to execute. 

As a result, Sorting and filtering values that are computed or transformed by a Response Data Transform fail because those values are not present at query-execution time. The platform attempts to sort or filter the raw Report Definition output, which may not contain the final displayed values. 

Any value computed or transformed by the DT is therefore not available for these operations, causing incorrect behavior, or empty filter dropdowns, or the error ".pxPages(X).FieldB does not exist or is not a valid entry". 

The official Pega documentation notes this limitation: 

"If you configured a response Data Transform or a post-load Activity to change the values that the report definition returns, the table might not display the values as expected." 

See Specifying a Data Page as queryable

Solution

The product is behaving as designed. 

Local Change

Option 1 — Remove the dynamic filter reference from the Report Definition

Replace the dynamic datapage.property filter condition in the Report Definition with a hardcoded static value, or restructure the filter logic so it does not depend on a Data Page property reference at query time. This allows the export engine to execute the query successfully. 

Note: This changes the filter logic and may not be suitable for all use cases. 

Option 2 — Disable "Allow querying any column" on the Data Page 

On the Data Page rule form, navigate to the Definition tab → Query options section and uncheck "Allow querying any column". 

Effects of this change: 

• Sorting and filtering are performed in-memory against the final Clipboard values after the Response Data Transform has executed, which restores correct behavior.

• The Data Page will no longer be available as a queryable source in Explore Data or Insights. 

References

Specifying Queryable Data Pages 

Specifying a Data Page as queryable