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30 lines
844 B
Markdown
30 lines
844 B
Markdown
---
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slug: /en/sql-reference/aggregate-functions/reference/maxmap
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sidebar_position: 143
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---
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# maxMap
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Syntax: `maxMap(key, value)` or `maxMap(Tuple(key, value))`
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Calculates the maximum from `value` array according to the keys specified in the `key` array.
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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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Returns a tuple of two arrays: keys and values calculated for the corresponding keys.
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Example:
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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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``` 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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