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52 lines
1.2 KiB
Markdown
52 lines
1.2 KiB
Markdown
---
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slug: /en/sql-reference/aggregate-functions/reference/maxmap
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sidebar_position: 165
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---
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# maxMap
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Calculates the maximum from `value` array according to the keys specified in the `key` array.
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**Syntax**
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```sql
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maxMap(key, value)
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```
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or
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```sql
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maxMap(Tuple(key, value))
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```
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Alias: `maxMappedArrays`
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:::note
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- Passing a tuple of keys and value arrays is identical to passing two arrays of keys and values.
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- The number of elements in `key` and `value` must be the same for each row that is totaled.
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:::
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**Parameters**
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- `key` — Array of keys. [Array](../../data-types/array.md).
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- `value` — Array of values. [Array](../../data-types/array.md).
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**Returned value**
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- Returns a tuple of two arrays: keys in sorted order, and values calculated for the corresponding keys. [Tuple](../../data-types/tuple.md)([Array](../../data-types/array.md), [Array](../../data-types/array.md)).
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**Example**
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Query:
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``` sql
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SELECT maxMap(a, b)
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FROM values('a Array(Char), b Array(Int64)', (['x', 'y'], [2, 2]), (['y', 'z'], [3, 1]))
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```
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Result:
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``` text
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┌─maxMap(a, b)───────────┐
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│ [['x','y','z'],[2,3,1]]│
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└────────────────────────┘
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```
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