假设我们有一个包含以下数据的数据集:
timestamp,col1
1533286270,1
1533286271,2
1533286272,3
1533286273,4
1533286274,5
我想得到前面的
col1
col1_prev
中的值能够比较它们。结果应该与 pandas.shift(-1)
相同.如何使用纯 SQL 查询实现此功能?
查询结果应如下所示:
timestamp,col1,col1_prev
1533286270,1,NULL
1533286271,2,1
1533286272,3,2
1533286273,4,3
1533286274,5,4
最佳答案
使用 lag()
函数是一种方式:
WITH
input AS (
SELECT
1533286270 AS timestamp,
1 AS col1
UNION ALL
SELECT
1533286271 AS timestamp,
2 AS col1
UNION ALL
SELECT
1533286272 AS timestamp,
3 AS col1
UNION ALL
SELECT
1533286273 AS timestamp,
4 AS col1
UNION ALL
SELECT
1533286274 AS timestamp,
5 AS col1 )
SELECT
timestamp,
col1,
LAG(col1) OVER(ORDER BY col1) AS col1_prev
FROM
input
关于google-bigquery - 如何在 BigQuery 中执行 Pandas 列转换?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/51669039/