Multiple aggregates with complex grouping combines several metrics (COUNT, SUM, AVG, MIN, MAX) across multiple business dimensions in a single efficient query.

**Why Multiple Aggregates:**

Business questions need multiple metrics:

- How many orders? (COUNT)

- Total revenue? (SUM)

- Average order value? (AVG)

- Price range? (MIN, MAX)

SQL computes all in one pass - much faster than separate queries.

**Complex Grouping:**

Group by multiple columns for finer analysis:

- Sales by region AND category

- Employees by department AND job level

- Revenue by plan AND time period

Each unique combination creates one result row.

**Canonical Pattern:**

SELECT

group_col1, group_col2,

COUNT(*) AS total,

SUM(amount) AS total_amount,

AVG(amount) AS avg_amount,

MIN(amount) AS min_amount,

MAX(amount) AS max_amount

FROM table

WHERE condition

GROUP BY group_col1, group_col2

HAVING aggregate_condition

ORDER BY metric DESC;

Foundation of BI and analytics. Used by data analysts, BI developers, and backend engineers building reporting systems and executive dashboards.

Powers every business dashboard - sales by region+category, employee metrics by department+level, revenue by plan+channel. Essential for comprehensive analytical reports.