“The number of output child records exceeds the allowed value. If the output file contains Long Text Area or Rich Text Area fields, the maximum number of child records is approximately 100-200 records. The upper limit depends on the length of the data type. Aggregate query has too many rows for direct assignment” is displayed.

In Ver.1, if the child records contain Long text Area/Rich Text Area merge fields, the subquery limitation of Salesforce is applied.

Salesforce Subquery Limitations (Applicable to Ver. 1 only)

If the child template contains Long Text Area or Rich Text Area merge fields, the maximum number of child records is approximately 50-200 records.
The maximum number of records depends on the length of the field and the number of fields.
These Limitations apply when Long Text Area or Rich Text Area fields are included, regardless of whether they have record values or not.
Since the application retrieves child records in a subquery and does not use For Loop, these limitations cannot be circumvented.

Resolution

Use Ver.2. In Ver.2, when a subquery restriction error occurs, only the child record where the error occurred is acquired by another method and there are no subquery limitations.
Set output conditions for child records and output them multiple times.

Salesforce Help

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