Aggregation
A SQL operation that computes a single result from a set of values, such as SUM, COUNT, AVG, MIN, or MAX.
In Depth
Aggregation in SQL refers to operations that compute a single summary value from a set of input values. The standard aggregate functions are COUNT (number of rows), SUM (total of values), AVG (average), MIN (smallest value), and MAX (largest value). Aggregations are typically combined with GROUP BY to compute summaries per group (e.g., total revenue per department) and HAVING to filter groups based on aggregate values. Advanced aggregations include PERCENTILE_CONT, STRING_AGG, ARRAY_AGG, and user-defined aggregate functions. Window functions (OVER clause) provide aggregations across a "window" of rows related to the current row without collapsing the result set—enabling running totals, moving averages, and rankings.
How AI for Database Helps
AI for Database automatically applies the right aggregations when you ask summary questions like "What is the total revenue by region?"
Related Terms
SQL
Structured Query Language—the standard programming language for managing and querying relational databases.
Window Function
A SQL function that performs calculations across a set of rows related to the current row without collapsing them.
Query Optimization
The process of improving a SQL query's execution speed and resource usage without changing the results.
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