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64 lines
1.4 KiB
Markdown
64 lines
1.4 KiB
Markdown
---
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slug: /en/sql-reference/aggregate-functions/reference/maxintersectionsposition
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sidebar_position: 164
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title: maxIntersectionsPosition
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---
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# maxIntersectionsPosition
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Aggregate function that calculates the positions of the occurrences of the [`maxIntersections` function](./maxintersections.md).
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The syntax is:
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```sql
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maxIntersectionsPosition(start_column, end_column)
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```
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**Arguments**
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- `start_column` – the numeric column that represents the start of each interval. If `start_column` is `NULL` or 0 then the interval will be skipped.
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- `end_column` - the numeric column that represents the end of each interval. If `end_column` is `NULL` or 0 then the interval will be skipped.
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**Returned value**
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Returns the start positions of the maximum number of intersected intervals.
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**Example**
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```sql
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CREATE TABLE my_events (
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start UInt32,
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end UInt32
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)
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Engine = MergeTree
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ORDER BY tuple();
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INSERT INTO my_events VALUES
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(1, 3),
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(1, 6),
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(2, 5),
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(3, 7);
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```
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The intervals look like the following:
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```response
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1 - 3
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1 - - - - 6
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2 - - 5
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3 - - - 7
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```
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Notice that three of these intervals have the value 4 in common, and that starts with the 2nd interval:
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```sql
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SELECT maxIntersectionsPosition(start, end) FROM my_events;
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```
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Response:
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```response
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2
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```
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In other words, the `(1,6)` row is the start of the 3 intervals that intersect, and 3 is the maximum number of intervals that intersect. |