Is it OK to edit a closed question, which does not have a single answer, to be a totally new question?

I am referring to this question: <https://stackoverflow.com/questions/40727626/mysql-syntax-error-or-access-violation-1055-column-name-isnt-in-group-by>
and its [edit history](https://stackoverflow.com/posts/40727626/revisions). The question was closed as a duplicate, but has no answer. The OP has edited it to create a new and different question. There is some controversy in the comments about whether or not this is OK.

Is it OK? What's our policy on this?