Hashed, searchable columns

[brycedarling]

I cannot find any documentation on how to make make hashed, searchable columns to go along with my encrypted column. Any help would be appreciated, thanks for the sweet lib!

[brycedarling]

Nevermind, found it in the docs after thinking to search for "hash" ;)

https://hexdocs.pm/cloak_ecto/Cloak.Ecto.PBKDF2.html#module-usage

Thank you!

[sveredyuk]

Hi, I have maybe a stupid question but is it possible to search with like or like by hashed fields?

[brycedarling]

@sveredyuk as far as I know, the hash is only useful for an exact equality lookup. a string like "this is some text" will be hashed to a value like DV5hk0ryjAsvSp3uFhhLog1tLp3/aA7/ttGFAq1yg9k= so it wouldn't be very useful to do a LIKE query on. when searching the table, the value you are looking for also gets hashed so that it can try find a row with that exact same matching hash.

[acrolink]

@sveredyuk as far as I know, the hash is only useful for an exact equality lookup. a string like "this is some text" will be hashed to a value like DV5hk0ryjAsvSp3uFhhLog1tLp3/aA7/ttGFAq1yg9k= so it wouldn't be very useful to do a LIKE query on. when searching the table, the value you are looking for also gets hashed so that it can try find a row with that exact same matching hash.

I have the same suspicion. Correct, true ? only exact full string match would work?

[sveredyuk]

Definitely. Using LIKE for hashed values will give you nothing. Or exact match or just use another soution

[jaimeiniesta]

I also came here looking for a way to search with LIKE in a hashed column, now I understand this is not possible. Maybe the documentation could say something like "findable" instead of "searchable" to imply that hashes allow you to find matching records, like exact emails or tokens, but not inside the content with LIKE.

A possible solution if there are not many records is to load the content in memory so that it's decrypted and then search with Elixir.