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65 lines
2.2 KiB
Markdown
65 lines
2.2 KiB
Markdown
---
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toc_priority: 311
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toc_title: sparkbar
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---
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# sparkbar {#sparkbar}
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The function plots a frequency histogram for values `x` and the repetition rate `y` of these values over the interval `[min_x, max_x]`.
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If no interval is specified, then the minimum `x` is used as the interval start, and the maximum `x` — as the interval end.
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**Syntax**
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``` sql
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sparkbar(width[, min_x, max_x])(x, y)
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```
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**Parameters**
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- `width` — The number of segments. Type: [Integer](../../../sql-reference/data-types/int-uint.md).
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- `min_x` — The interval start. Optional parameter.
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- `max_x` — The interval end. Optional parameter.
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**Arguments**
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- `x` — The field with values.
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- `y` — The field with the frequency of values.
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**Returned value**
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- The frequency histogram.
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**Example**
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Query:
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``` sql
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CREATE TABLE spark_bar_data (`cnt` UInt64,`event_date` Date) ENGINE = MergeTree ORDER BY event_date SETTINGS index_granularity = 8192;
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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');
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SELECT sparkbar(9)(event_date,cnt) FROM spark_bar_data;
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SELECT sparkbar(9,toDate('2020-01-01'),toDate('2020-01-10'))(event_date,cnt) FROM spark_bar_data;
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```
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Result:
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``` text
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┌─sparkbar(9)(event_date, cnt)─┐
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│ │
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│ ▁▅▄▃██▅ ▁ │
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│ │
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└──────────────────────────────┘
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┌─sparkbar(9, toDate('2020-01-01'), toDate('2020-01-10'))(event_date, cnt)─┐
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│ │
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│▁▄▄▂▅▇█▁ │
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│ │
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└──────────────────────────────────────────────────────────────────────────┘
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```
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