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WINDOW-FUNCTION-MAX

WINDOW FUNCTION MAX

description

LEAD() 方法用来计算窗口内的最大值。

MAX([DISTINCT | ALL] expression) [OVER (analytic_clause)]

example

计算从第一行到当前行之后一行的最大值

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