从字符串中提取子串

Question

在谷歌，BigQuery中，我需要拉即域之间的串**和**如示例波纹管 的字符串是列在“Site_Data”

灿谁来帮帮我？ 10倍！

Answer 1

参见下面的例子

#standardSQL 
WITH yourTable AS (
    SELECT '756-1__6565656565656, tagtype**unmapped,domain**www.sport.com,userarriveddirectly**False' AS Site_Data 
) 
SELECT 
    REGEXP_EXTRACT(Site_Data, r'domain\*\*(.*)\*\*') AS x, 
    Site_Data 
FROM yourTable 

Answer 2

是否所有的琴弦有格式？假设您总是需要**定界符后面的第三个字符串，有几个不同的选项。

1）使用SPLIT，如：

#standardSQL 
WITH SampleData AS (
    SELECT '756-1__67648582789116,tagtype**unmapped,domain**www.sport.com,userarriveddirectly**False' AS site_data 
) 
SELECT SPLIT(site_data, '**')[OFFSET(2)] AS visit_type 
FROM SampleData; 

2）使用REGEXP_EXTRACT，如：

#standardSQL 
WITH SampleData AS (
    SELECT '756-1__67648582789116,tagtype**unmapped,domain**www.sport.com,userarriveddirectly**False' AS site_data 
) 
SELECT REGEXP_EXTRACT(site_data, r'[^\*]+\*\*[^\*]+\*\*([^\*]+)') AS visit_type 
FROM SampleData; 

采取此基础上更进一步，如果你想分裂域和到达类型，您可以再次使用SPLIT：

#standardSQL 
WITH SampleData AS (
    SELECT '756-1__67648582789116,tagtype**unmapped,domain**www.sport.com,userarriveddirectly**False' AS site_data 
) 
SELECT 
    SPLIT(visit_type)[OFFSET(0)] AS domain, 
    SPLIT(visit_type)[OFFSET(1)] AS arrival_type 
FROM (
    SELECT SPLIT(site_data, '**')[OFFSET(2)] AS visit_type 
    FROM SampleData 
);