PARTITION BY user_id 表示数据按照user_id进行分区,ORDER BY order_date 指定了窗口内的行按order_date排序,而ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW则指定了窗口的范围是从分区第一行(用户的第一笔订单)到当前行(当前查询的订单)。 4. 解释示例中“rows between unbounded preceding”的作用 在示例中...
1.“rows between unbounded preceding and current row” 功能可实现与lead类似功能,但使用较为复杂,没lead好理解; 2.“rows between unbounded preceding and current row”与lead不同之处在于lead最后一条数据为NULL; 3.“rows between unbounded preceding and current row”、lead、以及IoT数仓中delta函数均可实...
-- 前1行_后1行sum(number)over(partitionbynameorderbytimestamprowsbetween1precedingand1following)assum_number_w2_row,-- 第1行_当前行sum(number)over(partitionbynameorderbytimestamprowsbetweenunboundedprecedingandcurrentrow)assum_number_w3
ROWS BETWEEN CURRENT ROW AND CURRENT ROW 5. 前 1 行到后 1 行:滑动窗口大小为 3。 ROWS BETWEEN 1 PRECEDING AND 1 FOLLOWING RANGE的用法 RANGE是基于逻辑值范围,按照排序列的值定义窗口范围: 1. 当前行及之前的所有行:累积逻辑值范围,例如累积求和。 RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW 2...
Oracle为这种情况提供了一个子句:rows between ... preceding and ... following。从字面上猜测它的意思是:在XXX之前和XXX之后的所有记录,实际情况如何让我们通过示例来验证: SQL>selectmonth, 2sum(tot_sales) month_sales, 3sum(sum(tot_sales))over(orderbymonth ...
rows between unbounded preceding and unbounded following) as total from trans t; select t.*,sum(amt) over(partition by accno ) as total from trans t; select t.*,sum(amt) over(partition by accno order by trans_dt rows between current row and unbounded following) as total ...
(ROWS | RANGE) BETWEEN CURRENT ROW AND (CURRENT ROW | (UNBOUNDED | [num]) FOLLOWING) 区别 ROWS BETWEEN 3 PRECEDING AND 4 FOLLOWING:表示在当前顺序的前提下,往前3行数据和往后4行数据,总计8行,当然这个8行不是绝对的,比如排序后的第一条数据亦或排序后的最后一条数据,根据行数判定肯定不会是8行。
ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING -- 第一行 - 最后一行 1. 2. 3. 4. 三、分析函数 1 聚合类 SUM()、AVG() 、MAX()、 MIN()、 COUNT() 功能和聚合函数一样 1 PARTITION BY 默认窗口的作用范围是从每个组的第一行到最后一行 ...
Oracle为这种情况提供了一个子句:rows between ... preceding and ... following。从字面上猜测它的意思是:在XXX之前和XXX之后的所有记录,实际情况如何让我们通过示例来验证:SQL > select month , 2 sum (tot_sales) month_sales, 3 sum ( sum (tot_sales)) over ( order by month 4 rows between un...
rows between函数: SQL语句中的rows between unbounded preceding and unbounded following ,其中: unbounded preceding:表示Long.MIN_VALUE,也就是可视当前行之前的所有数据 unbounded following:表示Long.MAX_VALUE,也就是可视当前行之后的所有数据 current row:表示当前行,也就是0 ...