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72 lines
2.3 KiB
Markdown
72 lines
2.3 KiB
Markdown
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---
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slug: /en/sql-reference/window-functions/first_value
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sidebar_label: first_value
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sidebar_position: 3
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---
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# first_value
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Returns the first non-NULL value evaluated within its ordered frame.
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**Syntax**
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```sql
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first_value (column_name)
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OVER ([[PARTITION BY grouping_column] [ORDER BY sorting_column]
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[ROWS or RANGE expression_to_bound_rows_withing_the_group]] | [window_name])
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FROM table_name
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WINDOW window_name as ([[PARTITION BY grouping_column] [ORDER BY sorting_column])
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```
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For more detail on window function syntax see: [Window Functions - Syntax](./index.md/#syntax).
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**Returned value**
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- The first non-NULL value evaluated within its ordered frame.
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**Example**
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In this example the `first_value` function is used to find the highest paid footballer from a fictional dataset of salaries of Premier League football players.
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Query:
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```sql
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DROP TABLE IF EXISTS salaries;
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CREATE TABLE salaries
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(
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`team` String,
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`player` String,
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`salary` UInt32,
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`position` String
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)
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Engine = Memory;
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INSERT INTO salaries FORMAT Values
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('Port Elizabeth Barbarians', 'Gary Chen', 196000, 'F'),
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('New Coreystad Archdukes', 'Charles Juarez', 190000, 'F'),
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('Port Elizabeth Barbarians', 'Michael Stanley', 100000, 'D'),
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('New Coreystad Archdukes', 'Scott Harrison', 180000, 'D'),
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('Port Elizabeth Barbarians', 'Robert George', 195000, 'M'),
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('South Hampton Seagulls', 'Douglas Benson', 150000, 'M'),
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('South Hampton Seagulls', 'James Henderson', 140000, 'M');
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```
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```sql
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SELECT player, salary,
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first_value(player) OVER (ORDER BY salary DESC) AS highest_paid_player
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FROM salaries;
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```
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Result:
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```response
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┌─player──────────┬─salary─┬─highest_paid_player─┐
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1. │ Gary Chen │ 196000 │ Gary Chen │
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2. │ Robert George │ 195000 │ Gary Chen │
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3. │ Charles Juarez │ 190000 │ Gary Chen │
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4. │ Scott Harrison │ 180000 │ Gary Chen │
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5. │ Douglas Benson │ 150000 │ Gary Chen │
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6. │ James Henderson │ 140000 │ Gary Chen │
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7. │ Michael Stanley │ 100000 │ Gary Chen │
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└─────────────────┴────────┴─────────────────────┘
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```
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