ClickHouse/docs/en/sql-reference/aggregate-functions/reference/argmax.md

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---
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slug: /en/sql-reference/aggregate-functions/reference/argmax
sidebar_position: 106
---
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# argMax
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Calculates the `arg` value for a maximum `val` value. If there are several different values of `arg` for maximum values of `val`, returns the first of these values encountered.
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Both parts the `arg` and the `max` behave as [aggregate functions](../index.md), they both [skip `Null`](../index.md#null-processing) during processing and return not-Null values if not-Null values are available.
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**Syntax**
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``` sql
argMax(arg, val)
```
**Arguments**
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- `arg` — Argument.
- `val` — Value.
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**Returned value**
- `arg` value that corresponds to maximum `val` value.
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Type: matches `arg` type.
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**Example**
Input table:
``` text
┌─user─────┬─salary─┐
│ director │ 5000 │
│ manager │ 3000 │
│ worker │ 1000 │
└──────────┴────────┘
```
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Query:
``` sql
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SELECT argMax(user, salary) FROM salary;
```
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Result:
``` text
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┌─argMax(user, salary)─┐
│ director │
└──────────────────────┘
```
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**Extended example**
```sql
CREATE TABLE test
(
a Nullable(String),
b Nullable(Int64)
)
ENGINE = Memory AS
SELECT *
FROM values(('a', 1), ('b', 2), ('c', 2), (NULL, 3), (NULL, NULL), ('d', NULL));
select * from test;
┌─a────┬────b─┐
│ a │ 1 │
│ b │ 2 │
│ c │ 2 │
│ ᴺᵁᴸᴸ │ 3 │
│ ᴺᵁᴸᴸ │ ᴺᵁᴸᴸ │
│ d │ ᴺᵁᴸᴸ │
└──────┴──────┘
select argMax(a, b), max(b) from test;
┌─argMax(a, b)─┬─max(b)─┐
│ b │ 3 │ -- argMax = b because it the first not-Null value, max(b) is from another row!
└──────────────┴────────┘
select argMax(tuple(a), b) from test;
┌─argMax(tuple(a), b)─┐
│ (NULL) │ -- Tuple allows to get Null value.
└─────────────────────┘
select (argMax((a, b), b) as t).1 argMaxA, t.2 argMaxB from test;
┌─argMaxA─┬─argMaxB─┐
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│ ᴺᵁᴸᴸ │ 3 │ -- you can use Tuple and get both (all - tuple(*)) columns for the according max(b)
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└─────────┴─────────┘
select argMax(a, b), max(b) from test where a is Null and b is Null;
┌─argMax(a, b)─┬─max(b)─┐
│ ᴺᵁᴸᴸ │ ᴺᵁᴸᴸ │ -- Nulls are not skipped because only Null values are available
└──────────────┴────────┘
select argMax(a, (b,a)) from test;
┌─argMax(a, tuple(b, a))─┐
│ c │ -- There are two rows with b=2, Tuple in the `Max` allows to get not the first `arg`
└────────────────────────┘
select argMax(a, tuple(b)) from test;
┌─argMax(a, tuple(b))─┐
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│ b │ -- Tuple can be used in `Max` to not skip Nulls in `Max`
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└─────────────────────┘
```
**See also**
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- [Tuple](../../data-types/tuple.md)