Thank you for reaching out.
Your observation is correct: concatenating M_Fname and F_Fname only creates a single composite key, so the report sorts them as one combined string. That’s why it doesn’t behave like a true “primary then secondary” sort.
The proper way in RDLC is to use multiple sort entries in the group’s Sorting settings. Keep your parameter-driven expression as the first sort (primary), then add another entry for the secondary field. This ensures the engine applies them in sequence first by the chosen field, then by the tiebreaker while preserving the current grouping. You can even add a third key (like an ID) for stability if needed.
Concatenation is a partial workaround, but multiple sort rows are the intended solution for predictable multi-level sorting.
Please let us know if you require any further assistance, we’re happy to help.
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