This page is a quick reference checkpoint for LEAD in BigQuery: behavior, syntax rules, edge cases, and a minimal example; plus the official vendor documentation.
LEAD returns a value from the next row in the window partition.
Returns the value of the expression for a subsequent row in the window frame; the return type matches the value_expression type. ([docs] section)
If this behavior feels unintuitive, the tutorial below explains the underlying pattern step-by-step.
LEAD(value_expression [, offset [, default_expression ]]) OVER (window_clause)
SELECT LEAD(sales) OVER (PARTITION BY region ORDER BY date) AS next_region_sales FROM sales_table;
If you came here to confirm syntax, you’re done. If you came here to get better at window functions, choose your next step.
LEAD is part of a bigger window-function pattern. If you want the “why”, start here: Lead Lag
Reading docs is useful. Writing the query correctly under pressure is the skill.
For the authoritative spec, use the vendor docs. This page is the fast “sanity check”.
View BigQuery Documentation →Looking for more functions across all SQL dialects? Visit the full SQL Dialects & Window Functions Documentation.