--- slug: /en/sql-reference/aggregate-functions/reference/sparkbar sidebar_position: 311 sidebar_label: sparkbar --- # sparkbar The function plots a frequency histogram for values `x` and the repetition rate `y` of these values over the interval `[min_x, max_x]`. Repetitions for all `x` falling into the same bucket are averaged, so data should be pre-aggregated. Negative repetitions are ignored. If no interval is specified, then the minimum `x` is used as the interval start, and the maximum `x` — as the interval end. Otherwise, values outside the interval are ignored. **Syntax** ``` sql sparkbar(buckets[, min_x, max_x])(x, y) ``` **Parameters** - `buckets` — The number of segments. Type: [Integer](../../../sql-reference/data-types/int-uint.md). - `min_x` — The interval start. Optional parameter. - `max_x` — The interval end. Optional parameter. **Arguments** - `x` — The field with values. - `y` — The field with the frequency of values. **Returned value** - The frequency histogram. **Example** Query: ``` sql CREATE TABLE spark_bar_data (`value` Int64, `event_date` Date) ENGINE = MergeTree ORDER BY event_date; INSERT INTO spark_bar_data VALUES (1,'2020-01-01'), (3,'2020-01-02'), (4,'2020-01-02'), (-3,'2020-01-02'), (5,'2020-01-03'), (2,'2020-01-04'), (3,'2020-01-05'), (7,'2020-01-06'), (6,'2020-01-07'), (8,'2020-01-08'), (2,'2020-01-11'); SELECT sparkbar(9)(event_date,cnt) FROM (SELECT sum(value) as cnt, event_date FROM spark_bar_data GROUP BY event_date); SELECT sparkbar(9, toDate('2020-01-01'), toDate('2020-01-10'))(event_date,cnt) FROM (SELECT sum(value) as cnt, event_date FROM spark_bar_data GROUP BY event_date); ``` Result: ``` text ┌─sparkbar(9)(event_date, cnt)─┐ │ ▂▅▂▃▆█ ▂ │ └──────────────────────────────┘ ┌─sparkbar(9, toDate('2020-01-01'), toDate('2020-01-10'))(event_date, cnt)─┐ │ ▂▅▂▃▇▆█ │ └──────────────────────────────────────────────────────────────────────────┘ ```