要解决这个问题,需要在PostgreSQL中使用窗口函数,对数据进行排序并筛选出最老的记录,然后再使用一个DEBOUNCE函数进行防抖操作,以确保结果不会被重复计算。代码示例如下:
WITH ranked AS (
SELECT id, value, ROW_NUMBER() OVER (ORDER BY created_at ASC) AS row_num
FROM my_table
),
debounced AS (
SELECT id, value
FROM ranked
WHERE row_num = 1 OR
EXTRACT(EPOCH FROM (created_at - LAG(created_at) OVER (ORDER BY created_at ASC))) >= 60
)
SELECT * FROM debounced;
这将从my_table中选择最老的记录,并使用一些时间范围(60秒)来确保每个记录只能被计算一次,从而实现防抖效果。