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56 lines
1.1 KiB
Markdown
56 lines
1.1 KiB
Markdown
---
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slug: /en/sql-reference/aggregate-functions/reference/first_value
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sidebar_position: 7
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---
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# first_value
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Selects the first encountered value, similar to `any`, but could accept NULL.
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## examples
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```sql
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insert into test_data (a,b) values (1,null), (2,3), (4, 5), (6,null)
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```
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### example1
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The NULL value is ignored at default.
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```sql
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select first_value(b) from test_data
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```
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```text
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┌─first_value_ignore_nulls(b)─┐
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│ 3 │
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└─────────────────────────────┘
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```
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### example2
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The NULL value is ignored.
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```sql
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select first_value(b) ignore nulls from test_data
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```
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```text
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┌─first_value_ignore_nulls(b)─┐
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│ 3 │
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└─────────────────────────────┘
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```
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### example3
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The NULL value is accepted.
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```sql
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select first_value(b) respect nulls from test_data
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```
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```text
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┌─first_value_respect_nulls(b)─┐
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│ ᴺᵁᴸᴸ │
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└──────────────────────────────┘
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```
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