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2.2 KiB
2.2 KiB
sidebar_position | sidebar_label |
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311 | 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]
.
If no interval is specified, then the minimum x
is used as the interval start, and the maximum x
— as the interval end.
Syntax
sparkbar(width[, min_x, max_x])(x, y)
Parameters
width
— The number of segments. Type: Integer.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:
CREATE TABLE spark_bar_data (`cnt` UInt64,`event_date` Date) ENGINE = MergeTree ORDER BY event_date SETTINGS index_granularity = 8192;
INSERT INTO spark_bar_data VALUES(1,'2020-01-01'),(4,'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 spark_bar_data;
SELECT sparkbar(9,toDate('2020-01-01'),toDate('2020-01-10'))(event_date,cnt) FROM spark_bar_data;
Result:
┌─sparkbar(9)(event_date, cnt)─┐
│ │
│ ▁▅▄▃██▅ ▁ │
│ │
└──────────────────────────────┘
┌─sparkbar(9, toDate('2020-01-01'), toDate('2020-01-10'))(event_date, cnt)─┐
│ │
│▁▄▄▂▅▇█▁ │
│ │
└──────────────────────────────────────────────────────────────────────────┘