| --- |
| { |
| "title": "WINDOW_FUNCTION_MAX", |
| "language": "en" |
| } |
| --- |
| |
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| |
| http://www.apache.org/licenses/LICENSE-2.0 |
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| |
| ## WINDOW FUNCTION MAX |
| ### description |
| |
| The LEAD() method is used to calculate the maximum value within the window. |
| |
| ```sql |
| MAX([DISTINCT | ALL] expression) [OVER (analytic_clause)] |
| ``` |
| |
| ### example |
| |
| Calculate the maximum value from the first row to the row after the current row |
| |
| ```sql |
| select x, property, |
| max(x) over |
| ( |
| order by property, x |
| rows between unbounded preceding and 1 following |
| ) as 'local maximum' |
| from int_t where property in ('prime','square'); |
| |
| | x | property | local maximum | |
| |---|----------|---------------| |
| | 2 | prime | 3 | |
| | 3 | prime | 5 | |
| | 5 | prime | 7 | |
| | 7 | prime | 7 | |
| | 1 | square | 7 | |
| | 4 | square | 9 | |
| | 9 | square | 9 | |
| ``` |
| |
| ### keywords |
| |
| WINDOW,FUNCTION,MAX |