i 有以下格式的表格
-------------
| id | item |
-------------
|1 | xxx |
|1 | xxx |
|1 | yyy |
|1 | xxx |
|1 | zzz |
|1 | xxx |
|1 | xxx |
|1 | xxx |
|1 | yyy |
|1 | xxx |
|1 | yyy |
|1 | xxx |
|1 | xxx |
|1 | xxx |
|1 | xxx |
|1 | xxx |
|1 | xxx |
|-----------|
I need to count maximum consecutive value of the item xxx. The above example its 6.
谢谢
SET @last = NULL, @max = 0, @count = 0;
SELECT @count := IF(item = @last, @count + 1, 0),
@max := GREATEST(@max, @count + 1),
@last := item
FROM my_table
ORDER BY ...
SELECT @max;
SET @last = NULL, @max = NULL, @count = NULL;
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