FILTER / SORT / UNIQUE — Excel guide

Dynamic arrays (365/2021+): formulas that return whole result sets and 'spill' into neighboring cells — live filtering, sorting, and deduplication with zero copies.

FILTER

Keep only the rows where a condition is true.

  • Contains-text: FILTER(data, ISNUMBER(SEARCH("pro", col))) — FILTER has no wildcards.
  • if_empty avoids #CALC! when nothing matches.
  • The include array must be exactly as tall as the data.

SORT

Return the array in order — original stays untouched.

  • SORTBY sorts by ranges you don't return — names ordered by a hidden score, multi-key sorts.
  • sort_order -1 = descending.

UNIQUE

The distinct values — a live, self-updating dedupe.

  • Unlike Remove Duplicates, it updates as data changes and never touches the source.
  • Multi-column input dedupes whole ROWS (distinct pairs).
  • #SPILL! means the landing zone is occupied — clear the blocking cells.
  • Reference a whole spill with # (=E2#): self-sizing dropdowns and follow-on formulas.

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