BigQuery REGEXP_EXTRACT from URL - extract parameters values

Question

I need to use REGEXP_EXTRACT on various URLs i have in BigQuery and extract different strings from them.

For exmaple, i have this URL:

url = https://www.whatever.com/record-a-beautiful-and-professional-voice-over?sec_context=recommendation&context_alg=nodes&sec_context_referrer=search

I want to use the BigQuery REGEXP_EXTRACT function and extract the string that comes after the parameter named context_alg= (presented after the first & in the URL). Meaning - my output will be nodes .

( context_alg is a parameter in the URL and always has the same name)

So actually I need to use something like:

REGEXP_EXTRACT(url, "REGEXP that bring back 'nodes')

Thank you !

Answer 1

尝试下面的BigQuery

REGEXP_EXTRACT(url, r'context_alg=([^?&#]*)')  

Answer 2

If you need to extract all parameters from a URL, you can also use REGEXP_EXTRACT_ALL as follows:

REGEXP_EXTRACT_ALL(query,r'(?:\?|&)((?:[^=]+)=(?:[^&]*))') as params

This will return the result as an array (see How to extract URL parameters as ARRAY in Google BigQuery ):