bigquery sql 中的数据清理从浮点数变为整数

Question

您好，我有一个 table，我想在其中将列中的值从浮点数更改为整数并替换值并将其保留为字符串。我最好怎么做？

table如下：

id	discount	product
1	10	dettol soap
2	10.0	dettol soap green
3	0	dettol soap red
4	x	dettol soap blue
5		dettol soap yellow
6	5	dettol soap beige
9	13.3210282172312131	dettol soap white

我想把折扣table刷成一样table

id	discount	product
1	10	dettol soap
2	10	dettol soap green
3	0	dettol soap red
4	0	dettol soap blue
5	0	dettol soap yellow
6	5	dettol soap beige
9	13	dettol soap white

我有的是 select ID , cast(cast(discount as integer) as string) ，产品来自 table

如何将非数字和空格替换为 0，将小数替换为整数并转换为字符串并将值替换为当前 table？

Answer 1

考虑一下：

SELECT CAST(IFNULL(CAST(SAFE_CAST(x AS FLOAT64) AS INT64), 0) AS STRING) AS discount 
  FROM UNNEST(['10', '10.0', '0', 'x', '', '5', '13.3210282172312131']) x;

或者，你可以用正则表达式试试。

SELECT IFNULL(REGEXP_EXTRACT(x, r'^[0-9]+'), '0') discount
  FROM UNNEST(['10', '10.0', '0', 'x', '', '5', '13.3210282172312131']) x;

输出：

Answer 2

考虑以下

select * 
  replace(
    format('%.0f', ifnull(safe_cast(discount AS float64), 0))
  as discount)
from your_table

如果应用于您问题中的示例数据 - 输出为

bigquery sql 中的数据清理从浮点数变为整数

Data cleaning in bigquery sql changing from float to integer

google-bigquery