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Update first_value, last_value with possibility to use RESPECT NULLS

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Blargian 2024-07-10 22:16:03 +02:00
parent e02d14263b
commit 41633cabb2
3 changed files with 20 additions and 6 deletions
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11
docs/en/sql-reference/window-functions/first_value.md
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# first_value
Returns the first non-NULL value evaluated within its ordered frame.
Returns the first value evaluated within its ordered frame. By default, NULL arguments are skipped, however the `RESPECT NULLS` modifier can be used to override this behaviour.
**Syntax**
```sql
first_value (column_name)
first_value (column_name) [RESPECT NULLS]
OVER ([[PARTITION BY grouping_column] [ORDER BY sorting_column]
[ROWS or RANGE expression_to_bound_rows_withing_the_group]] | [window_name])
FROM table_name
WINDOW window_name as ([[PARTITION BY grouping_column] [ORDER BY sorting_column])
```
Alias: `any`.
:::note
Using the optional modifier `RESPECT NULLS` after `first_value(column_name)` will ensure that `NULL` arguments are not skipped.
See [NULL processing](../aggregate-functions/index.md/#null-processing) for more information.
:::
For more detail on window function syntax see: [Window Functions - Syntax](./index.md/#syntax).
**Returned value**

4
docs/en/sql-reference/window-functions/index.md
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@ -77,8 +77,8 @@ WINDOW window_name as ([[PARTITION BY grouping_column] [ORDER BY sorting_column]
These functions can be used only as a window function.
- [`row_number()`](./row_number.md) - Number the current row within its partition starting from 1.
- [`first_value(x)`](./first_value.md) - Return the first non-NULL value evaluated within its ordered frame.
- [`last_value(x)`](./last_value.md) - Return the last non-NULL value evaluated within its ordered frame.
- [`first_value(x)`](./first_value.md) - Return the first value evaluated within its ordered frame.
- [`last_value(x)`](./last_value.md) - Return the last value evaluated within its ordered frame.
- [`nth_value(x, offset)`](./nth_value.md) - Return the first non-NULL value evaluated against the nth row (offset) in its ordered frame.
- [`rank()`](./rank.md) - Rank the current row within its partition with gaps.
- [`dense_rank()`](./dense_rank.md) - Rank the current row within its partition without gaps.

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docs/en/sql-reference/window-functions/last_value.md
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# last_value
Returns the last non-NULL value evaluated within its ordered frame.
Returns the last value evaluated within its ordered frame. By default, NULL arguments are skipped, however the `RESPECT NULLS` modifier can be used to override this behaviour.
**Syntax**
```sql
last_value (column_name)
last_value (column_name) [RESPECT NULLS]
OVER ([[PARTITION BY grouping_column] [ORDER BY sorting_column]
[ROWS or RANGE expression_to_bound_rows_withing_the_group]] | [window_name])
FROM table_name
WINDOW window_name as ([[PARTITION BY grouping_column] [ORDER BY sorting_column])
```
Alias: `anyLast`.
:::note
Using the optional modifier `RESPECT NULLS` after `first_value(column_name)` will ensure that `NULL` arguments are not skipped.
See [NULL processing](../aggregate-functions/index.md/#null-processing) for more information.
:::
For more detail on window function syntax see: [Window Functions - Syntax](./index.md/#syntax).
**Returned value**