BigQuery QUALIFY Clause: Filter Window Functions Directly
By Sharon Ben-Moshe · August 16, 2026 · 1 min read
Sharon Ben-Moshe is the founder of sqlfmt, a browser-based SQL formatter and validator with misspelled-keyword suggestions across PostgreSQL, MySQL, SQLite, SQL Server, and BigQuery.
Use BigQuery QUALIFY to filter window-function results without an outer subquery. Learn evaluation order, top-N-per-group patterns, and portability.
Quick answer
BigQuery's QUALIFY clause filters results after window functions are evaluated. Use it to keep a rank, row number, or other window-based condition without wrapping the calculation in a subquery. QUALIFY requires a window function in the clause itself or in the SELECT list.
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