How to search data in MySQL database?

I am using nextant 1.0.3 in nextCloud 11. I have configured Solr to be able to index data in a MySQL database. (ref: http://blog.comperiosearch.com/blog/2014/08/28/indexing-database-using-solr/)
However, since there is no a “database” option in “external storage” backends to select, how can I search data content from the database?

That’s interesting, I might add this feature to Nextant

Hi, I learned that “searching within SQL database” is added to nextant github (https://github.com/nextcloud/nextant/issues/120). May I know any update of this please?