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

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---
slug: /en/sql-reference/aggregate-functions/reference/last_value
sidebar_position: 8
---
# first_value
Selects the last encountered value, similar to `anyLast`, but could accept NULL.
## examples
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```sql
insert into test_data (a,b) values (1,null), (2,3), (4, 5), (6,null)
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```
### example1
The NULL value is ignored at default.
```sql
select last_value(b) from test_data
```
```text
┌─last_value_ignore_nulls(b)─┐
│ 5 │
└────────────────────────────┘
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```
### example2
The NULL value is ignored.
```sql
select last_value(b) ignore nulls from test_data
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```
```text
┌─last_value_ignore_nulls(b)─┐
│ 5 │
└────────────────────────────┘
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```
### example3
The NULL value is accepted.
```sql
select last_value(b) respect nulls from test_data
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```
```text
┌─last_value_respect_nulls(b)─┐
│ ᴺᵁᴸᴸ │
└─────────────────────────────┘
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```