Is there a minimum length for search terms?

[Tennman]

My community uses a lot of 3 letter abbreviations in posts.  If I do a search, for example "ECM", there are no results for my search even though I know the ECM has been used in dozens of posts.  Is there a setting I need to change to allow searches 3 characters in length?  Thanks for your help.

[Nathan Explosion]

MySQL - 4 characters, default.

To change it, https://dev.mysql.com/doc/refman/5.6/en/fulltext-fine-tuning.html#fulltext-word-length

No idea what the default and equivalent is with ElasticSearch.

[Tennman]

Thanks for the link. That explains it.  My community is on a shared server.  Can I change the MySQL default to 3 characters in my cPanel or will I have to contact my hosting provider?

[Nathan Explosion]

I suggest you ask your hosting provider that question.

[Tennman]

Thanks Nathan.

[HelloWorld]

Hi all,

I just thought that I would add an answer on this, as @Nathan Explosion's answer helped me see things clearly, but MariaDB's documentation (in my case, Maria 10.2.6, InnoDB engine) did not.

It states that (see that link) :

Quote

Words less than 4 characters in length (3 or less) will not be stored in the fulltext index.

Yet, on the page regarding the variable innodb_ft_min_token_size :

Quote

innodb_ft_min_token_size
Minimum length of words stored in an InnoDB FULLTEXT INDEX 
Default Value: 3

3 was the value of the innodb_ft_min_token_size variable configured on my server (no more, no less). Still, the search would not return topics such as "FA Cup" when I would search for "Cup" on topics' titles only. Neither would it return a topic named "David de Gea", for instance, when looking for "Gea" or "de Gea".

I thought that maybe, innodb_ft_min_token_size was the maximum length of words not stored when building the index, rather than the minimum length of words stored? So I changed the value to 2 rather than 3, restarted MariaDB, and the index is now rebuilding (it took me some time to notice the "Rebuild search index" button in the top right corner of the IPB search settings page).

I will let you know how it ends.

[HelloWorld]

Update : it still does not work.

@Tennman did you figure out how to solve your issue, please?