Is there a way to measure string similarity in Google BigQuery

Question

I\'m wondering if anyone knows of a way to measure string similarity in BigQuery.

Seems like would be a neat function to have.

My case is i need to compare

Answer 1

Levenshtein via JS would be the way to go. You can use the algorithm to get absolute string distance, or convert it to a percentage similarity by simply calculating abs(strlen - distance / strlen).

The easiest way to implement this would be to define a Levenshtein UDF that takes two inputs, a and b, and calculates the distance between them. The function could return a, b, and the distance.

To invoke it, you'd then pass in the two URLs as columns aliased to 'a' and 'b':

SELECT a, b, distance
FROM
  Levenshtein(
     SELECT
       some_url AS a, other_url AS b
     FROM
       your_table
  )