Add checking for hh/where when (seq clauses) is nil

[slipset]

(-> (hh/delete-from :foo)
      (hh/where xs))

Is a potential foot gun when (seq xs) is nil, since it translates to DELETE FROM foo
It would be nice to add detection for this in the :checking functionality described in https://cljdoc.org/d/com.github.seancorfield/honeysql/2.2.891/doc/getting-started?q=checking#format-options

I'd be happy to work on a PR for this
Having looked at the code, I might have been a bit optimistic with regards to my happiness to work on a PR for this.
The checking bit is done in the format part of honey, and the format bit is somewhat involved it seems.
It would be much easier it seems to do this checking in hh/where :)

[seancorfield]

You can't do the checking in the helpers -- not everyone uses them and there are many ways to build the data structure that is the DSL.

The checking needs to be added to the formatters for :delete-from and :update in a way that will catch when there are no qualifying conditions, but I will need to do quite a bit of digging/analysis of SQL syntax implications before I can do that.

As usual, with SQL stuff, it's harder than it looks 😄

[seancorfield]

Adding checks to :delete, :delete-from, and :update for a non-empty :where clause is relatively straightforward but I don't want :checking :basic or :checking :strict to invalid legal code so I'm asking on Slack about it.

[orestis]

We are using :delete-from with no where clause, in a single place: a full-sync ETL pipeline that first clears all the rows, then re-inserts them from the source DB. I wouldn't mind having to add a :where [:= 1 1] or similar, assuming that has no performance implications in most DBs.

I think doing some checking is a good way to avoid messing up during REPL excursions.

[slipset]

@orestis for such a use case, truncate table foo might be a better solution.

[seancorfield]

This has been added as a :basic check.